Flash Flood Prediction Program
by f2p2@udfcd.org
Time: 115 PM Wed May 31, 2023
Forecaster: Brad Simmons
-------------------------
Internal Message Status
Flash Flood Prediction Program
-------------------------
MESSAGE 1'S ISSUED FOR THE ENTIRE DISTRICT
Message 1’s have been issued for the entire District and will be
valid until 10:00pm this evening.
Thunderstorms have initiated over the foothills and will begin to
spread out onto the plains over the next couple hours. Thunderstorm
coverage will be widely scattered with typical weak to moderate
thunderstorms producing light to moderate rain and gusty winds.
Stronger thunderstorms will be capable of producing brief heavy
rainfall and may become severe with large hail and winds in excess of
50mph. A nearly stationary thunderstorm that forms along a gust front
or wind convergence boundary will produce the greatest threat for an
extended period of heavy rain today that may lead to excessive runoff
and possibly flash flooding.
1-3 rounds of showers and thunderstorms are expected to move through
the District into the evening. Best chances for moderate to strong
thunderstorms will be through 9 or 10pm then additional showers and
weaker thunderstorms will be possible into the early overnight period.
STORM RAINFALL POTENTIAL AND DURATION: Weak to moderate thunderstorms
will produce 0.1-0.3” of rain in 10-30 minutes. Strong thunderstorms
will have the potential to produce rainfall rates of 0.3-0.8” in
10-30 minutes.
WORST CASE SCENARIO: A nearly stationary strong thunderstorm may
result in up to 1.5” of rain in 45-75 minutes.
COUNTY
MESSAGE
VALID TIMES
PRIME TIME
Boulder County
1
100 PM TO 1000 PM
200 PM TO 900 PM
Jefferson County
1
100 PM TO 1000 PM
200 PM TO 900 PM
Broomfield County
1
100 PM TO 1000 PM
200 PM TO 900 PM
Douglas County
1
100 PM TO 1000 PM
200 PM TO 900 PM
Adams County
1
100 PM TO 1000 PM
200 PM TO 900 PM
Denver County
1
100 PM TO 1000 PM
200 PM TO 900 PM
DIA
1
100 PM TO 1000 PM
200 PM TO 900 PM
Arapahoe County
1
100 PM TO 1000 PM
200 PM TO 900 PM
the City of Aurora
1
100 PM TO 1000 PM
200 PM TO 900 PM
Arvada
1
100 PM TO 1000 PM
200 PM TO 900 PM
Wheat Ridge
1
100 PM TO 1000 PM
200 PM TO 900 PM
Lakewood
1
100 PM TO 1000 PM
200 PM TO 900 PM
County-specific Quantitative
Precipitation Outlook PRECIPITATION TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
Current TO 1000 PM WED
0.1" (85%) to 0.3" (55%) to 0.8" (25%)
ISSUED
Arapahoe
Current TO 1000 PM WED
0.1" (85%) to 0.3" (55%) to 0.8" (25%)
ISSUED
Boulder
Current TO 1000 PM WED
0.1" (85%) to 0.3" (55%) to 0.8" (25%)
ISSUED
Broomfield
Current TO 1000 PM WED
0.1" (85%) to 0.3" (55%) to 0.8" (25%)
ISSUED
Denver
Current TO 1000 PM WED
0.1" (85%) to 0.3" (55%) to 0.8" (25%)
ISSUED
Douglas
Current TO 1000 PM WED
0.1" (85%) to 0.3" (55%) to 0.8" (25%)
ISSUED
Jefferson
Current TO 1000 PM WED
0.1" (85%) to 0.3" (55%) to 0.8" (25%)
ISSUED
Foothills above 6500ft
Boulder
Current TO 1000 PM WED
0.1" (95%) to 0.3" (65%) to 0.8" (35%)
ISSUED
Douglas
Current TO 1000 PM WED
0.1" (95%) to 0.3" (65%) to 0.8" (35%)
ISSUED
Jefferson
Current TO 1000 PM WED
0.1" (95%) to 0.3" (65%) to 0.8" (35%)
ISSUED
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
1 year, 6 months
Flash Flood Prediction Program
by f2p2@udfcd.org
Time: 914 AM Wed May 31, 2023
Forecaster: Brad Simmons
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
THUNDERSTORM CHANCES INCREASE TODAY AND THE WEATHER PATTERN WILL
BECOME EVEN MORE ACTIVE INTO THE UPCOMING WEEKEND
Temperatures will continue to run slightly above seasonal averages
with highs this afternoon in the upper 70’s to lower 80’s over the
plains. Normal high for Denver today is 78 degrees. Sunny skies this
morning will become mostly cloudy to cloudy at times this afternoon as
storms move off the foothills and onto the plains.
Thunderstorms will first develop over the foothills between noon and
1pm. Upper level steering winds from SW to NE will push the storms
onto the plains between 1-3pm. Widely scattered thunderstorms will
then continue likely into the evening with best chances for
thunderstorms through about 9pm. After 9pm additional rain showers and
possibly a weak thunderstorm will remain possible beyond midnight into
the early morning hours on Thursday.
Typical weak to moderate thunderstorms today will produce light to
moderate rain and gusty winds. Stronger thunderstorms will be capable
of producing brief heavy rainfall and may become severe with large
hail and winds in excess of 50mph. A nearly stationary thunderstorm
that forms along a gust front or wind convergence boundary will
produce the greatest threat for an extended period of heavy rain
today.
STORM RAINFALL POTENTIAL AND DURATION: Weak to moderate thunderstorms
will produce 0.1-0.3” of rain in 10-30 minutes. Strong thunderstorms
will have the potential to produce rainfall rates of 0.3-0.8” in
10-30 minutes.
WORST CASE SCENARIO: A nearly stationary strong thunderstorm may
result in up to 1.5” of rain in 45-75 minutes.
A LOOK AHEAD: Temperatures will decrease and thunderstorm chances will
increase daily from Thursday and Friday into Saturday. Thunderstorms
characteristics will modify with each passing day as the threat for
severe weather from stronger thunderstorms lowers while the threat for
heavy rainfall and flooding increases. Saturday and Sunday appear to
be the peak in the rain shower and thunderstorm activity.
Precipitation may favor a soaking rain at times Saturday and Sunday
versus thunderstorms as temperatures will be cool in the 60s. Should
thunderstorms develop they will be very capable of producing heavy
rain. Not much change in the weather pattern into next week as the
onslaught of unusually wet weather continues this spring season.
LOCATION
PRIME TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
200 PM TO 900 PM
0.1" (70%) to 0.3" (50%) to 0.8" (20%)
MOD
Arapahoe
200 PM TO 900 PM
0.1" (70%) to 0.3" (50%) to 0.8" (20%)
MOD
Broomfield
200 PM TO 900 PM
0.1" (70%) to 0.3" (50%) to 0.8" (20%)
MOD
Denver
200 PM TO 900 PM
0.1" (70%) to 0.3" (50%) to 0.8" (20%)
MOD
Boulder
100 PM TO 900 PM
0.1" (70%) to 0.3" (50%) to 0.8" (20%)
MOD
Douglas
100 PM TO 900 PM
0.1" (70%) to 0.3" (50%) to 0.8" (20%)
MOD
Jefferson
100 PM TO 900 PM
0.1" (70%) to 0.3" (50%) to 0.8" (20%)
MOD
Foothills above 6500ft
Boulder
1200 PM TO 900 PM
0.1" (80%) to 0.3" (50%) to 0.8" (20%)
MOD
Douglas
1200 PM TO 900 PM
0.1" (80%) to 0.3" (50%) to 0.8" (20%)
MOD
Jefferson
1200 PM TO 900 PM
0.1" (80%) to 0.3" (50%) to 0.8" (20%)
MOD
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
1 year, 6 months
Flash Flood Prediction Program
by f2p2@udfcd.org
Time: 905 AM Tue May 30, 2023
Forecaster: Brad Simmons
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
SLIGHTLY ABOVE NORMAL TEMPERATURES WITH ISOLATED AFTERNOON
THUNDERSTORMS
Temperatures will continue to run slightly above normal over the
District today with afternoon highs over the plains reaching the lower
80’s with 70’s in the Front Range foothills. Normal high for
Denver today is 77 degrees. Sunny skies this morning will give way to
partly to mostly cloudy skies this afternoon as clouds build and
thunderstorms develop.
Thunderstorms will initiate over the foothills by around noon then
spread out onto the plains between 1-2pm. Thunderstorm coverage will
be isolated with typical storms producing light to briefly moderate
rain. Storms will strengthen along and E of I-25 where there is better
surface moisture with some storms possibly becoming strong to severe
with brief heavy rainfall, gusty winds and hail. By 8 or 9pm the storm
activity is expected to have moved to the E of the District.
Generally, 1-2 rounds of storms are expected but with isolated
coverage the storms will be hit or miss. Best chances for brief
moderate to heavy rain will favor eastern areas of the District with
lesser chances into the foothills.
Upper level steering winds will result in typical storm motions from
WSW to ENE at 15-20mph. Thunderstorms that form along an outflow
boundary may result in some storms moving more slowly or erratically
before being carried away by the upper level winds. After 8 or 9pm the
thunderstorm activity is expected to have moved E of the District with
dry conditions developing for the later evening and overnight period.
STORM RAINFALL POTENTIAL AND DURATION: Weak to moderate thunderstorms
will produce a trace to 0.2” of rain in 10-30 minutes. Strong
thunderstorms will have the potential to produce rainfall rate of
0.2-0.5” in 10-30 minutes.
WORST CASE SCENARIO: A slower moving or briefly stationary strong
thunderstorm along an outflow boundary may result in rainfall rates of
0.3-0.7” in 10-30 minutes and up to 1.0” of rain in 45-60 minutes.
A LOOK AHEAD: A slight increase in thunderstorm activity is expected
Wednesday with widely scattered thunderstorms in the afternoon and
early evening. Stronger storms may become severe with hail/gusty winds
and carry the potential for brief heavy rain. Better chances for
showers and thunderstorms on Thursday with cooler temperatures and the
threat for heavy rainfall increasing. Scattered to numerous showers
and thunderstorms are likely on Friday and Saturday with stronger
storms capable of producing heavy rain that may lead to excessive
runoff. Temperatures will be below normal and may struggle to reach 70
degrees on Friday and Saturday.
LOCATION
PRIME TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
100 PM TO 800 PM
Trace (75%) to 0.2" (50%) to 0.5" (25%)
MOD
Arapahoe
100 PM TO 800 PM
Trace (75%) to 0.2" (50%) to 0.5" (25%)
MOD
Boulder
100 PM TO 800 PM
Trace (75%) to 0.2" (50%) to 0.5" (25%)
LOW
Broomfield
100 PM TO 800 PM
Trace (70%) to 0.2" (40%) to 0.5" (20%)
LOW
Denver
100 PM TO 800 PM
Trace (75%) to 0.2" (50%) to 0.5" (25%)
MOD
Douglas
100 PM TO 800 PM
Trace (75%) to 0.2" (50%) to 0.5" (25%)
MOD
Jefferson
100 PM TO 800 PM
Trace (70%) to 0.2" (40%) to 0.5" (20%)
LOW
Foothills above 6500ft
Boulder
1200 PM TO 800 PM
Trace (80%) to 0.2" (50%) to 0.5" (15%)
LOW
Douglas
1200 PM TO 800 PM
Trace (80%) to 0.2" (50%) to 0.5" (15%)
LOW
Jefferson
1200 PM TO 800 PM
Trace (80%) to 0.2" (50%) to 0.5" (15%)
LOW
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
1 year, 6 months
Flash Flood Prediction Program
by f2p2@udfcd.org
Time: 502 PM Mon May 29, 2023
Forecaster: Justin Brooks
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
GUST FRONT FROM THE SOUTHEAST HAS INCREASED STORM CHANCES THIS
AFTERNOON
A gust front from the southeast has moved into the District
triggering a line of storms along north/northeastern portions of the
District at this time. These storms will likely be pulse-like, with
some moderate to brief heavy rain. The largest threat from these
storms will be a quick 0.5” in 10-30 minutes, rather than any
long-lasting rainfall. This will result in an increase to a LOW chance
for Message 1’s to be issued this afternoon and into the early
evening.
The best chance for storms will be now through 8pm with skies
gradually clearing as the sun sets. Overnight lows will dip into the
upper 40’s to low 50’s on the plains with mid 40’s along the
foothills.
STORM RAINFALL POTENTIAL AND DURATION: Typical rain showers and
isolated weak thunderstorms will produce TR-0.25” in 10-30 minutes.
A moderate to strong thunderstorm could produce 0.25-0.50” in 10-30
minutes.
WORST CASE SCENARIO: A stationary thunderstorm formed along an outflow
boundary, or training of moderate to heavy rain showers has the
potential to produce up to 1.0” in 60 minutes.
A LOOK AHEAD: Afternoon and evening storm chances will continue
throughout the week, with likely a low threat for heavy rainfall in
the upcoming days. Similar conditions remain in place tomorrow with
high temperatures around 80 degrees. Best chance for storms will be
the typical 2-8pm with chances decreasing into the later evening.
LOCATION
PRIME TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
Current TO 800 PM MON
Trace (50%) to 0.25" (25%) to 0.5" (10%)
LOW
Arapahoe
Current TO 800 PM MON
Trace (50%) to 0.25" (25%) to 0.5" (10%)
LOW
Boulder
Current TO 800 PM MON
Trace (50%) to 0.25" (25%) to 0.5" (10%)
LOW
Broomfield
Current TO 800 PM MON
Trace (50%) to 0.25" (25%) to 0.5" (10%)
LOW
Denver
Current TO 800 PM MON
Trace (50%) to 0.25" (25%) to 0.5" (10%)
LOW
Douglas
Current TO 800 PM MON
Trace (50%) to 0.25" (25%) to 0.5" (10%)
LOW
Jefferson
Current TO 800 PM MON
Trace (50%) to 0.25" (25%) to 0.5" (10%)
LOW
Foothills above 6500ft
Boulder
Current TO 800 PM MON
Trace (50%) to 0.25" (25%) to 0.5" (10%)
LOW
Douglas
Current TO 800 PM MON
Trace (50%) to 0.25" (25%) to 0.5" (10%)
LOW
Jefferson
Current TO 800 PM MON
Trace (50%) to 0.25" (25%) to 0.5" (10%)
LOW
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
1 year, 7 months
Flash Flood Prediction Program
by f2p2@udfcd.org
Time: 855 AM Mon May 29, 2023
Forecaster: Brad Simmons
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
TEMPERATURES INCREASE SLIGHTLY WITH ISOLATED AFTERNOON THUNDERSTORMS
Temperatures will increase slightly over the District today with
afternoon highs topping out in the low to mid 80’s over the plains
which is about 5 degrees above normal. The normal high for Denver
today is 77 degrees.
Most of the thunderstorm activity this afternoon is expected to remain
to the N of the District but there will still be a slight chance for
an isolated thunderstorm or two. Storms that manage to develop today
will generally produce gusty winds and light rain/sprinkles, but a
stronger storm could produce a brief burst of moderate rain over a
small geographical area. The majority of the District will end up on
the drier side today.
Best chances for thunderstorm activity will be between 1pm and sunset.
Upper level steering winds are from W to E at around 20mph. After 8 or
9pm dry conditions are expected for the remainder of the evening and
overnight period.
STORM RAINFALL POTENTIAL AND DURATION: Rain showers and isolated weak
to briefly moderate thunderstorms will produce a trace to 0.2” of
rain.
WORST CASE SCENARIO: Outflow from storms to the N and NE of the
District push back westward increasing surface moisture resulting in a
briefly strong thunderstorm with the potential to produce 0.2-0.5”
of rain in 10-30 minutes.
A LOOK AHEAD: A slight uptick in moisture on Tuesday and the aid of a
weak upper level disturbance will lead to a few more storms with
widely scattered thunderstorms in the afternoon and evening.
Thunderstorms will generally produce light to brief moderate rain and
possibly some hail. Temperatures will be similar to today. Moisture
increases further on Wednesday and storms should be more numerous in
the afternoon and evening with some storms potentially producing heavy
rainfall and severe weather. Temperatures will back off a few degrees
with increased cloud cover. Cooler still for Thursday and a good
chance for afternoon showers and thunderstorms, some of which may
contain heavy rain.
LOCATION
PRIME TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
100 PM TO 800 PM
Trace (50%) to 0.1" (25%) to 0.2" (15%)
NONE
Arapahoe
100 PM TO 800 PM
Trace (40%) to 0.1" (20%) to 0.2" (10%)
NONE
Boulder
100 PM TO 800 PM
Trace (60%) to 0.1" (30%) to 0.2" (15%)
NONE
Broomfield
100 PM TO 800 PM
Trace (40%) to 0.1" (20%) to 0.2" (10%)
NONE
Denver
100 PM TO 800 PM
Trace (40%) to 0.1" (20%) to 0.2" (10%)
NONE
Douglas
100 PM TO 800 PM
Trace (50%) to 0.1" (25%) to 0.2" (10%)
NONE
Jefferson
100 PM TO 800 PM
Trace (50%) to 0.1" (25%) to 0.2" (10%)
NONE
Foothills above 6500ft
Boulder
1200 PM TO 800 PM
Trace (60%) to 0.1" (30%) to 0.2" (15%)
NONE
Douglas
1200 PM TO 800 PM
Trace (60%) to 0.1" (30%) to 0.2" (15%)
NONE
Jefferson
1200 PM TO 800 PM
Trace (60%) to 0.1" (30%) to 0.2" (15%)
NONE
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
1 year, 7 months
Flash Flood Prediction Program
by f2p2@udfcd.org
Time: 859 AM Sun May 28, 2023
Forecaster: Brad Simmons
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
NEAR NORMAL TEMPERATURES WITH A REDUCTION IN THUNDERSTORM ACTIVITY
EXPECTED TODAY
Temperatures will be at or slightly above normal over the District
today with afternoon highs in the upper 70s to around 80 degrees. The
normal high for Denver today is 77 degrees.
A reduction in thunderstorm activity is expected today compared to
previous days with isolated afternoon thunderstorms. Overall, there is
a decrease in moisture at the surface and aloft which will result in
typical storms only producing light to briefly moderate rain. There is
a low chance of a stronger storm should a moisture boundary push back
to the W during the afternoon. Should a stronger storm be able to
develop brief heavy rain will be possible as well as more hail. Storms
that develop today will move from WSW to ENE at around 20mph. The
relatively fast storm motions will also help to reduce point rainfall
amounts today.
The best chances for thunderstorms will be between 1-8pm.
Thunderstorms will initialize over the foothills first then move onto
the plains after 2pm with some areas likely missing out on storm
activity today. After 8 or 9pm conditions are expected to dry out for
the remainder of the evening and overnight period.
STORM RAINFALL POTENTIAL AND DURATION: Rain showers and weak
thunderstorms will produce a trace to 0.1” of rain. Moderate to
briefly strong thunderstorms will have the potential to produce
rainfall rates of 0.1-0.4” in 10-30 minutes.
WORST CASE SCENARIO: A strong, slower moving thunderstorm may result
in rainfall rates of 0.3-0.7” in 10-30 minutes and up to 1.0” in
45-60 minutes.
A LOOK AHEAD: Similar setup on Monday with isolated afternoon and
evening thunderstorms with typical storms producing light to briefly
moderate rain. A stronger storm cannot be completely ruled out.
Temperatures Monday will climb to above normal with highs in the lower
80’s over the plains. Thunderstorm activity will begin to increase
Tuesday and increase further on Wednesday and Thursday with better
chances for stronger storms capable of producing heavy rainfall and
possibly severe weather.
LOCATION
PRIME TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
200 PM TO 800 PM
Trace (60%) to 0.2" (30%) to 0.4" (15%)
LOW
Arapahoe
200 PM TO 800 PM
Trace (60%) to 0.2" (30%) to 0.4" (15%)
LOW
Broomfield
200 PM TO 800 PM
Trace (60%) to 0.2" (30%) to 0.4" (15%)
LOW
Denver
200 PM TO 800 PM
Trace (60%) to 0.2" (30%) to 0.4" (15%)
LOW
Boulder
130 PM TO 800 PM
Trace (70%) to 0.2" (35%) to 0.4" (15%)
LOW
Douglas
130 PM TO 800 PM
Trace (75%) to 0.2" (35%) to 0.4" (15%)
LOW
Jefferson
130 PM TO 800 PM
Trace (70%) to 0.2" (35%) to 0.4" (15%)
LOW
Foothills above 6500ft
Boulder
100 PM TO 800 PM
Trace (80%) to 0.2" (40%) to 0.4" (20%)
LOW
Douglas
100 PM TO 800 PM
Trace (80%) to 0.2" (40%) to 0.4" (20%)
LOW
Jefferson
100 PM TO 800 PM
Trace (80%) to 0.2" (40%) to 0.4" (20%)
LOW
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
1 year, 7 months
Flash Flood Prediction Program
by f2p2@udfcd.org
Time: 933 PM Sat May 27, 2023
Forecaster: Brad Simmons
-------------------------
Internal Message Status
Flash Flood Prediction Program
-------------------------
MESSAGE 1'S HAVE BEEN ALLOWED TO EXPIRE AT 9:30PM/ADDITIONAL RAIN
SHOWERS CONTINUE POSSIBLE
Message 1’s have been allowed to expire at 9:30pm as the threat of
heavy rainfall has ended for the day.
The surface wind convergence has washed out and storms are pushing
eastward. Now that we are after sunset temperatures are cooling and no
additional strong thunderstorm activity is expected this evening.
Isolated rain showers and possibly a weak thunderstorm cannot be ruled
out until around midnight. Best chances for additional shower activity
will be over southern and eastern areas of the District as drier air
makes pushes in from the west.
A slight decrease in thunderstorm activity is expected on Sunday but
the storms that form in the afternoon will still be capable of
becoming strong to severe and will have the potential to produce brief
heavy rainfall and large hail.
STORM RAINFALL POTENTIAL AND DURATION: Rain showers will produce a
trace to 0.1” of rain. An isolated weak thunderstorm will have the
potential to produce 0.1-0.3” in 10-30 minutes.
COUNTY
MESSAGE
VALID TIMES
PRIME TIME
County-specific Quantitative
Precipitation Outlook PRECIPITATION TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
Current TO 1159 PM SAT
Trace (60%) to 0.1" (30%) to 0.3" (10%)
NONE
Arapahoe
Current TO 1159 PM SAT
Trace (60%) to 0.1" (30%) to 0.3" (10%)
NONE
Boulder
Current TO 1159 PM SAT
Trace (40%) to 0.1" (20%) to 0.3" (5%)
NONE
Broomfield
Current TO 1159 PM SAT
Trace (40%) to 0.1" (20%) to 0.3" (5%)
NONE
Denver
Current TO 1159 PM SAT
Trace (60%) to 0.1" (30%) to 0.3" (10%)
NONE
Douglas
Current TO 1159 PM SAT
Trace (60%) to 0.1" (30%) to 0.3" (10%)
NONE
Jefferson
Current TO 1159 PM SAT
Trace (40%) to 0.1" (20%) to 0.3" (5%)
NONE
Foothills above 6500ft
Boulder
Current TO 1159 PM SAT
Trace (40%) to 0.1" (20%) to 0.3" (5%)
NONE
Douglas
Current TO 1159 PM SAT
Trace (40%) to 0.1" (20%) to 0.3" (5%)
NONE
Jefferson
Current TO 1159 PM SAT
Trace (40%) to 0.1" (20%) to 0.3" (5%)
NONE
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
1 year, 7 months
Flash Flood Prediction Program
by f2p2@udfcd.org
Time: 754 PM Sat May 27, 2023
Forecaster: Brad Simmons
-------------------------
Internal Message Status
Flash Flood Prediction Program
-------------------------
MESSAGE 1'S HAVE BEEN EXTENDED UNTIL 9:30PM FOR THE ENTIRE DISTRICT
Message 1’s have been extended until 9:30pm for the entire
District.
Surface wind convergence resides over the District currently and is
generating new thunderstorm development. Stronger thunderstorms may
still produce moderate to brief heavy rainfall into the evening as
well as hail and gusty winds. A large thunderstorm or training of
thunderstorm cells will be the most likely culprits for extended
periods of heavy rain over the next 1-2 hours. Typical storms will
move from SW to NE at around 20mph, but stronger storms may move more
slowly.
Thunderstorm activity is expected to decrease between 9-10pm and
eventually move east of the District. If thunderstorms still persist
past 9:30pm Message 1’s may be extended further.
STORM RAINFALL POTENTIAL AND DURATION: Weak thunderstorms will produce
0.1-0.3" of rain. Moderate to strong thunderstorms will have the
potential to produce rainfall rates of 0.3-0.8” in 10-30 minutes.
WORST CASE SCENARIO: A slow moving strong thunderstorm or large
thunderstorm cell may result in up to 1.5” of rain in 45-60 minutes
COUNTY
MESSAGE
VALID TIMES
PRIME TIME
Arapahoe County
1
319 PM TO 930 PM
330 PM TO 900 PM
the City of Aurora
1
319 PM TO 930 PM
330 PM TO 900 PM
DIA
1
319 PM TO 930 PM
330 PM TO 900 PM
Denver County
1
319 PM TO 930 PM
330 PM TO 900 PM
Adams County
1
319 PM TO 930 PM
330 PM TO 900 PM
Douglas County
1
319 PM TO 930 PM
330 PM TO 900 PM
Broomfield County
1
319 PM TO 930 PM
330 PM TO 900 PM
Jefferson County
1
319 PM TO 930 PM
330 PM TO 900 PM
Boulder County
1
319 PM TO 930 PM
330 PM TO 900 PM
Lakewood
1
319 PM TO 930 PM
330 PM TO 900 PM
Wheat Ridge
1
319 PM TO 930 PM
330 PM TO 900 PM
Arvada
1
319 PM TO 930 PM
330 PM TO 900 PM
County-specific Quantitative
Precipitation Outlook PRECIPITATION TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
Current TO 930 PM SAT
0.1" (75%) to 0.3" (40%) to 0.8" (20%)
ISSUED
Arapahoe
Current TO 930 PM SAT
0.1" (75%) to 0.3" (40%) to 0.8" (20%)
ISSUED
Boulder
Current TO 930 PM SAT
0.1" (60%) to 0.3" (30%) to 0.8" (10%)
ISSUED
Broomfield
Current TO 930 PM SAT
0.1" (60%) to 0.3" (30%) to 0.8" (10%)
ISSUED
Denver
Current TO 930 PM SAT
0.1" (80%) to 0.3" (40%) to 0.8" (20%)
ISSUED
Douglas
Current TO 930 PM SAT
0.1" (80%) to 0.3" (40%) to 0.8" (20%)
ISSUED
Jefferson
Current TO 930 PM SAT
0.1" (80%) to 0.3" (40%) to 0.8" (20%)
ISSUED
Foothills above 6500ft
Boulder
Current TO 930 PM SAT
0.1" (60%) to 0.3" (30%) to 0.8" (10%)
ISSUED
Douglas
Current TO 930 PM SAT
0.1" (60%) to 0.3" (30%) to 0.8" (10%)
ISSUED
Jefferson
Current TO 930 PM SAT
0.1" (60%) to 0.3" (30%) to 0.8" (10%)
ISSUED
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
1 year, 7 months
Flash Flood Prediction Program
by f2p2@udfcd.org
Time: 442 PM Sat May 27, 2023
Forecaster: Brad Simmons
-------------------------
Internal Message Status
Flash Flood Prediction Program
-------------------------
MESSAGE 1'S NOW ISSUED FOR THE ENTIRE DISTRICT
Message 1’s now includes all areas of the District and will be
valid until 8:00pm this evening.
Outflow boundaries from previous storms are pushing moisture back to
the W and is increasing the surface moisture which will help fuel
thunderstorms. Northern and eastern areas of the District still have
better chances for a stronger storm this afternoon and early evening
as the moisture is more abundant in this zone. Storms over the
foothills are expected to be weaker than plains storms. Much like the
past few days the stronger storms will be capable of producing hail as
well as brief moderate to heavy rainfall that may lead to excessive
runoff roadways. Most storms will be weak to moderate with just a
slight chance for a stronger thunderstorm.
Best chances for thunderstorms will be over the next few hours then
chances decrease after 7:30pm. Typical storms will move from SW to NE
at around 20mph and the relatively fast storm motions will help to
reduce point rainfall amounts. A large thunderstorm or a slower moving
thunderstorm will be the culprits for extended periods of heavy rain
should they develop.
STORM RAINFALL POTENTIAL AND DURATION: Weak thunderstorms will produce
0.1-0.3" of rain. Moderate to strong thunderstorms will have the
potential to produce rainfall rates of 0.3-0.9” in 10-30 minutes.
WORST CASE SCENARIO: A slow moving strong thunderstorm or large
thunderstorm cell may result in up to 1.5” of rain in 45-60 minutes
COUNTY
MESSAGE
VALID TIMES
PRIME TIME
Arvada
1
Current TO 800 PM
Current TO 700 PM
the City of Aurora
1
Current TO 800 PM
Current TO 700 PM
Arapahoe County
1
Current TO 800 PM
Current TO 700 PM
DIA
1
Current TO 800 PM
Current TO 700 PM
Denver County
1
Current TO 800 PM
Current TO 700 PM
Adams County
1
Current TO 800 PM
Current TO 700 PM
Douglas County
1
Current TO 800 PM
Current TO 700 PM
Broomfield County
1
Current TO 800 PM
Current TO 700 PM
Jefferson County
1
Current TO 800 PM
Current TO 700 PM
Boulder County
1
Current TO 800 PM
Current TO 700 PM
Wheat Ridge
1
Current TO 800 PM
Current TO 700 PM
Lakewood
1
Current TO 800 PM
Current TO 700 PM
County-specific Quantitative
Precipitation Outlook PRECIPITATION TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
Current TO 800 PM SAT
0.1" (80%) to 0.3" (40%) to 0.9" (20%)
ISSUED
Arapahoe
Current TO 800 PM SAT
0.1" (75%) to 0.3" (35%) to 0.9" (15%)
ISSUED
Boulder
Current TO 800 PM SAT
0.1" (85%) to 0.3" (50%) to 0.9" (25%)
ISSUED
Broomfield
Current TO 800 PM SAT
0.1" (85%) to 0.3" (50%) to 0.9" (25%)
ISSUED
Denver
Current TO 800 PM SAT
0.1" (80%) to 0.3" (40%) to 0.9" (20%)
ISSUED
Douglas
Current TO 800 PM SAT
0.1" (75%) to 0.3" (30%) to 0.9" (15%)
ISSUED
Jefferson
Current TO 800 PM SAT
0.1" (75%) to 0.3" (30%) to 0.9" (15%)
ISSUED
Foothills above 6500ft
Boulder
Current TO 800 PM SAT
0.1" (60%) to 0.3" (30%) to 0.9" (10%)
ISSUED
Douglas
Current TO 800 PM SAT
0.1" (60%) to 0.3" (30%) to 0.9" (10%)
ISSUED
Jefferson
Current TO 800 PM SAT
0.1" (60%) to 0.3" (30%) to 0.9" (10%)
ISSUED
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
1 year, 7 months
Flash Flood Prediction Program
by f2p2@udfcd.org
Time: 332 PM Sat May 27, 2023
Forecaster: Brad Simmons
-------------------------
Internal Message Status
Flash Flood Prediction Program
-------------------------
MESSAGES ISSUED FOR PORTIONS OF THE DISTRICT
Message 1’s have been issued for Adams, Arapahoe, Boulder,
Broomfield and Denver Counties and will be valid until 8:00pm this
evening.
Moisture has scoured out over S and SW areas of the District over
Douglas and Jefferson Counties with higher moisture values over
northern areas of the District. Northern areas of the District will
have better chances for a stronger storm this afternoon and early
evening. Much like the past few days the stronger storms will be
capable of producing hail as well as brief moderate to heavy rainfall
that may lead to excessive runoff roadways.
Best chances for thunderstorms will be over the next 3-4 hours then
chances decrease after 7:00pm. Typical storms will move from SW to NE
at around 20mph and the relatively fast storm motions will help to
reduce point rainfall amounts. A large thunderstorm or a slower moving
thunderstorm will be the culprits for extended periods of heavy rain.
Should an outflow boundary from northern storms push back to the south
and replenish surface moisture additional Message 1’s may be issued
for Jefferson and Douglas Counties.
STORM RAINFALL POTENTIAL AND DURATION: Weak thunderstorms will produce
0.1-0.3" of rain. Moderate to strong thunderstorms will have the
potential to produce rainfall rates of 0.3-0.9” in 10-30 minutes.
WORST CASE SCENARIO: A slow moving strong thunderstorm or large
thunderstorm cell may result in up to 1.5” of rain in 45-60 minutes
COUNTY
MESSAGE
VALID TIMES
PRIME TIME
Broomfield County
1
Current TO 800 PM
Current TO 700 PM
Boulder County
1
Current TO 800 PM
Current TO 700 PM
DIA
1
Current TO 800 PM
Current TO 700 PM
Arapahoe County
1
Current TO 800 PM
Current TO 700 PM
the City of Aurora
1
Current TO 800 PM
Current TO 700 PM
Arvada
1
Current TO 800 PM
Current TO 700 PM
Wheat Ridge
1
Current TO 800 PM
Current TO 700 PM
Lakewood
1
Current TO 800 PM
Current TO 700 PM
Denver County
1
Current TO 800 PM
Current TO 700 PM
Adams County
1
Current TO 800 PM
Current TO 700 PM
County-specific Quantitative
Precipitation Outlook PRECIPITATION TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
Current TO 800 PM SAT
0.1" (80%) to 0.3" (40%) to 0.9" (20%)
ISSUED
Arapahoe
Current TO 800 PM SAT
0.1" (70%) to 0.3" (30%) to 0.9" (10%)
ISSUED
Boulder
Current TO 800 PM SAT
0.1" (85%) to 0.3" (50%) to 0.9" (25%)
ISSUED
Broomfield
Current TO 800 PM SAT
0.1" (85%) to 0.3" (50%) to 0.9" (25%)
ISSUED
Denver
Current TO 800 PM SAT
0.1" (80%) to 0.3" (40%) to 0.9" (20%)
ISSUED
Douglas
Current TO 800 PM SAT
0.1" (50%) to 0.3" (25%) to 0.9" (5%)
LOW
Jefferson
Current TO 800 PM SAT
0.1" (50%) to 0.3" (25%) to 0.9" (5%)
LOW
Foothills above 6500ft
Boulder
Current TO 800 PM SAT
0.1" (60%) to 0.3" (30%) to 0.9" (10%)
ISSUED
Douglas
Current TO 800 PM SAT
0.1" (60%) to 0.3" (30%) to 0.9" (10%)
LOW
Jefferson
Current TO 800 PM SAT
0.1" (60%) to 0.3" (30%) to 0.9" (10%)
LOW
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
1 year, 7 months