Flash Flood Prediction Program
by f2p2@udfcd.org
Time: 853 AM Wed June 30, 2021
Forecaster: Brad Simmons
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
SLOW STORM MOTIONS AND AMPLE MOISTURE = INGREDIENTS FOR HEAVY RAINFALL
PRODUCING THUNDERSTORMS
-
Moisture is on the increase today, the only question is whether or
not there will be any significant storm coverage within District
boundaries... Light upper level winds from the SW at 10mph or less and
ample surface moisture with dew points in the upper 40's to lower 50's
will result in thunderstorms that develop today having the potential
to produce extended periods of moderate and heavy rainfall.
-
Thunderstorms will first develop over the foothills and Palmer
Divide by around noon or shortly after. With light steering winds and
a lack of a trigger over the plains the storms are expected to favor
the higher terrain. Rain cooled outflow from foothill storms or the
development of a surface wind convergence line over the plains will
likely be needed to initiate convection within the District itself.
Between 2-4pm a gust front from foothill storms or the set-up of a
surface wind convergence line may develop or a combination of the two
and thunderstorms will become more likely over the plains.
-
The foothills and Palmer Divide stand the best chance for stronger
storms today with a lesser chance over the plains, however the plains
storms will be just as capable of producing heavy rain, the overall
threat is just lower. Prime time for thunderstorms today is from
2-8pm, beyond 8pm any thunderstorm activity is expected to be weak
with conditions trending dry for the overnight period.
STORM RAINFALL POTENTIAL AND DURATION: Rain showers and weak
thunderstorms will produce 0.1-0.4" in 15-45 minutes. Moderate to
strong thunderstorms will have the potential to produce 0.4-1.6" in
15-45 minutes.
WORST CASE SCENARIO: A stationary strong thunderstorm may result in up
to 2.5" of rain in 60-90 minutes.
A LOOK AHEAD: Thunderstorm chances increase all areas of the District
on Thursday with scattered to numerous thunderstorms expected during
the afternoon and evening. There is a high likelihood of excessive
runoff and possibly flash flooding as moisture levels continue to rise
and storm motions remain very slow. Not much change on Friday with
scattered to numerous thunderstorms with the potential for heavy
rainfall. There will likely be a flooding event of some type over the
next few days but the severity and location cannot be pinpointed until
the events begin to unfold.
LOCATION
PRIME TIME
45-Minute Rainfall
and % Probability Message
Potential
Plains
Â
Â
Â
Adams
200 PM TO 800 PM
0.1" (65%) to 0.4" (30%) to 1.0" (15%)
MOD
Arapahoe
200 PM TO 800 PM
0.1" (65%) to 0.4" (30%) to 1.0" (15%)
MOD
Broomfield
200 PM TO 800 PM
0.1" (65%) to 0.4" (30%) to 1.0" (15%)
MOD
Denver
200 PM TO 800 PM
0.1" (65%) to 0.4" (30%) to 1.0" (15%)
MOD
Boulder
100 PM TO 800 PM
0.1" (75%) to 0.4" (50%) to 1.0" (25%)
MOD
Douglas
100 PM TO 800 PM
0.1" (80%) to 0.4" (60%) to 1.0" (30%)
MOD
Jefferson
100 PM TO 800 PM
0.1" (75%) to 0.4" (50%) to 1.0" (25%)
MOD
Foothills above 6500ft
Â
Â
Â
Boulder
1200 PM TO 800 PM
0.1" (95%) to 0.4" (75%) to 1.0" (35%)
HIGH
Douglas
1200 PM TO 800 PM
0.1" (95%) to 0.4" (75%) to 1.0" (35%)
HIGH
Jefferson
1200 PM TO 800 PM
0.1" (95%) to 0.4" (75%) to 1.0" (35%)
HIGH
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 Â Â Â F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
3 years, 5 months
Flash Flood Prediction Program
by f2p2@udfcd.org
Time: 805 PM Tue June 29, 2021
Forecaster: Justin Brooks
-------------------------
Internal Message Status
Flash Flood Prediction Program
-------------------------
MESSAGE 1'S WILL BE ALLOWED TO EXPIRE AT 9:00 PM
-
Message 1's will be allowed to expire at 9:00pm as the threat for
heavy rainfall across the District has come to an end for the day.
-
Rain showers have started to dissipate over the District and will
continue to do so over the next hour or so with very few light
lingering rain showers along the foothills.
-
Skies will gradually clear through the overnight and into tomorrow
morning. Another chance for widely scattered rain
showers/thunderstorms tomorrow afternoon with high temperatures
reaching the low to mid 80's.
STORM RAINFALL POTENTIAL AND DURATION: Typical light rain showers will
produce a trace to 0.10" in 10-30 minutes.
WORST CASE SCENARIO: A moderate rain showers has the potential to
produce 0.10-0.3" in 30-60 minutes.
COUNTY
MESSAGE
VALID TIMES
PRIME TIME
Wheat Ridge
1
Current TO 900 PM
Current TO 900 PM
Lakewood
1
Current TO 900 PM
Current TO 900 PM
Arvada
1
Current TO 900 PM
Current TO 900 PM
the City of Aurora
1
Current TO 900 PM
Current TO 900 PM
Arapahoe County
1
Current TO 900 PM
Current TO 900 PM
DIA
1
Current TO 900 PM
Current TO 900 PM
Denver County
1
Current TO 900 PM
Current TO 900 PM
Adams County
1
Current TO 900 PM
Current TO 900 PM
Douglas County
1
Current TO 900 PM
Current TO 900 PM
Broomfield County
1
Current TO 900 PM
Current TO 900 PM
Jefferson County
1
Current TO 900 PM
Current TO 900 PM
Boulder County
1
Current TO 900 PM
Current TO 900 PM
County-specific Quantitative
Precipitation Outlook PRECIPITATION TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Â
Â
Â
Adams
Current TO 1000 PM TUE
Trace (20%) to 0.1" (10%) to 0.3" (0%)
NONE
Arapahoe
Current TO 1000 PM TUE
Trace (20%) to 0.1" (10%) to 0.3" (0%)
NONE
Boulder
Current TO 1000 PM TUE
Trace (20%) to 0.1" (10%) to 0.3" (0%)
NONE
Broomfield
Current TO 1000 PM TUE
Trace (20%) to 0.1" (10%) to 0.3" (0%)
NONE
Denver
Current TO 1000 PM TUE
Trace (20%) to 0.1" (10%) to 0.3" (0%)
NONE
Douglas
Current TO 1000 PM TUE
Trace (20%) to 0.1" (10%) to 0.3" (0%)
NONE
Jefferson
Current TO 1000 PM TUE
Trace (20%) to 0.1" (10%) to 0.3" (0%)
NONE
Foothills above 6500ft
Â
Â
Â
Boulder
Current TO 1000 PM TUE
Trace (20%) to 0.1" (10%) to 0.3" (5%)
NONE
Douglas
Current TO 1000 PM TUE
Trace (20%) to 0.1" (10%) to 0.3" (5%)
NONE
Jefferson
Current TO 1000 PM TUE
Trace (20%) to 0.1" (10%) to 0.3" (5%)
NONE
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 Â Â Â F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
3 years, 5 months
Flash Flood Prediction Program
by f2p2@udfcd.org
Time: 405 PM Tue June 29, 2021
Forecaster: Justin Brooks
-------------------------
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 effective until
9pm.
-
Slow moving to nearly stationary thunderstorms have pushed a rain
cooled outflow boundary eastward and onto the plains. Nearly
stationary rain showers and isolated thunderstorms have formed around
the Chatfield area and will slowly build outward from this area to the
north and east with rain showers to isolated thunderstorms possible
throughout the District for the rest of this afternoon and evening.
-
Moderate to strong thunderstorms will be capable of producing heavy
rainfall that may lead to excessive runoff. Best chances for
thunderstorms will be over the next 4-5hours.
STORM RAINFALL POTENTIAL AND DURATION: Weak to moderate thunderstorms
will produce 0.3-0.9" in 10-30 minutes.
WORST CASE SCENARIO: A stationary moderate to strong thunderstorm may
result in up to 2.5" of rain in 60-90 minutes.
COUNTY
MESSAGE
VALID TIMES
PRIME TIME
Douglas County
1
Current TO 900 PM
Current TO 800 PM
Adams County
1
Current TO 900 PM
Current TO 800 PM
Denver County
1
Current TO 900 PM
Current TO 800 PM
DIA
1
Current TO 900 PM
Current TO 800 PM
Arapahoe County
1
Current TO 900 PM
Current TO 800 PM
the City of Aurora
1
Current TO 900 PM
Current TO 800 PM
Arvada
1
Current TO 900 PM
Current TO 800 PM
Wheat Ridge
1
Current TO 900 PM
Current TO 800 PM
Lakewood
1
Current TO 900 PM
Current TO 800 PM
Broomfield County
1
Current TO 900 PM
Current TO 800 PM
Jefferson County
1
Current TO 900 PM
Current TO 800 PM
Boulder County
1
Current TO 900 PM
Current TO 800 PM
County-specific Quantitative
Precipitation Outlook PRECIPITATION TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Â
Â
Â
Adams
Current TO 900 PM TUE
0.1" (30%) to 0.3" (20%) to 0.9" (5%)
ISSUED
Arapahoe
Current TO 900 PM TUE
0.1" (40%) to 0.3" (30%) to 0.9" (10%)
ISSUED
Boulder
Current TO 900 PM TUE
0.1" (65%) to 0.3" (40%) to 0.9" (20%)
ISSUED
Broomfield
Current TO 900 PM TUE
0.1" (50%) to 0.3" (40%) to 0.9" (10%)
ISSUED
Denver
Current TO 900 PM TUE
0.1" (50%) to 0.3" (40%) to 0.9" (10%)
ISSUED
Douglas
Current TO 900 PM TUE
0.1" (75%) to 0.3" (50%) to 0.9" (25%)
ISSUED
Jefferson
Current TO 900 PM TUE
0.1" (75%) to 0.3" (50%) to 0.9" (25%)
ISSUED
Foothills above 6500ft
Â
Â
Â
Boulder
Current TO 900 PM TUE
0.1" (75%) to 0.3" (50%) to 0.9" (25%)
ISSUED
Douglas
Current TO 900 PM TUE
0.1" (75%) to 0.3" (50%) to 0.9" (25%)
ISSUED
Jefferson
Current TO 900 PM TUE
0.1" (75%) to 0.3" (50%) to 0.9" (25%)
ISSUED
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 Â Â Â F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
3 years, 5 months
Flash Flood Prediction Program
by f2p2@udfcd.org
Time: 308 PM Tue June 29, 2021
Forecaster: Brad Simmons
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
FOOTHILL THUNDERSTORMS MAY SUPPLY TRIGGER FOR STORMS ON THE PLAINS
LATER THIS AFTERNOON/EVENING
-
Slow moving to nearly stationary thunderstorms over the foothills of
Jefferson County may push a rain cooled outflow boundary eastward onto
the plains shortly. This rain cooled outflow boundary/gust front may
be able to overcome a warm layer of air aloft and generate new storm
development over the plains in the coming hours.
-
Thunderstorms if they develop will be slow moving and capable of
producing moderate to heavy rainfall for extended periods of time.
There is no indication that storms are imminent but may develop over
the coming hours if conditions come together just right.
-
Best chances for thunderstorm activity continues to be over the
foothills through about 8pm this evening.
STORM RAINFALL POTENTIAL AND DURATION: Weak to moderate thunderstorms
will produce 0.3-0.9" in 10-30 minutes. Strong thunderstorms will have
the potential to produce 0.5-1.5" in 10-30 minutes.
WORST CASE SCENARIO: A stationary moderate to strong thunderstorm may
result in up to 2.5" of rain in 60-90 minutes.
A LOOK AHEAD: We will tack on a few more degrees to high temperatures
on Wednesday and add a little more moisture. With more heat and
moisture to work with there will be a better chance for afternoon
thunderstorms, some of which may contain heavy rainfall. Thursday and
Friday will feature a high likelihood of afternoon and evening
thunderstorms with the potential to produce heavy rainfall that may
result in excessive runoff and flash flooding.
LOCATION
PRIME TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Â
Â
Â
Adams
400 PM TO 800 PM
0.1" (60%) to 0.3" (30%) to 0.9" (15%)
MOD
Arapahoe
400 PM TO 800 PM
0.1" (60%) to 0.3" (30%) to 0.9" (15%)
MOD
Boulder
400 PM TO 800 PM
0.1" (65%) to 0.3" (40%) to 0.9" (20%)
MOD
Broomfield
400 PM TO 800 PM
0.1" (60%) to 0.3" (30%) to 0.9" (15%)
MOD
Denver
400 PM TO 800 PM
0.1" (60%) to 0.3" (30%) to 0.9" (15%)
MOD
Douglas
400 PM TO 800 PM
0.1" (65%) to 0.3" (40%) to 0.9" (20%)
MOD
Jefferson
400 PM TO 800 PM
0.1" (65%) to 0.3" (40%) to 0.9" (20%)
MOD
Foothills above 6500ft
Â
Â
Â
Boulder
Current TO 800 PM TUE
0.1" (95%) to 0.3" (70%) to 0.9" (30%)
MOD
Douglas
Current TO 800 PM TUE
0.1" (95%) to 0.3" (70%) to 0.9" (30%)
MOD
Jefferson
Current TO 800 PM TUE
0.1" (95%) to 0.3" (70%) to 0.9" (30%)
MOD
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 Â Â Â F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
3 years, 5 months
Flash Flood Prediction Program
by f2p2@udfcd.org
Time: 934 AM Tue June 29, 2021
Forecaster: Brad Simmons
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
WARM LAYER OF AIR ALOFT MAY PUT A LID ON THUNDERTSORM DEVELOPMENT OVER
THE PLAINS?
-
A warm layer of air aloft at around 20,000ft is expected to suppress
thunderstorm activity over the plains today with any shower or
thunderstorm activity generally limited to the foothills and Palmer
Divide. Late in the day moisture will increase from the S and a stray
storm cannot be completely ruled out over the plains but they will be
far and few between. Temperatures today will nudge upwards a few
degrees into the mid 70's to around 80 over the I-25 corridor.
-
Shower and weak to moderate thunderstorm activity will develop over
the higher terrain W of the District during the early afternoon.
Increasing moisture from the S or an outflow from foothill storms may
be able to generate isolated showers and weak thunderstorms over the
plains by 3 or 4pm. With ample surface moisture in place if a
thunderstorm is able to develop it will have the potential for
moderate rainfall.
-
The current impression is that the warm layer of air aloft will hold
and keep thunderstorm activity limited to the higher terrain W and S
of the District with any activity within the District being weak and
short lived. If the warm layer of air aloft erodes the HPO may need to
be updated to increase the chances for thunderstorms and heavy
rainfall.
STORM RAINFALL POTENTIAL AND DURATION: Rain showers and weak
thunderstorms will produce a trace to 0.2" in 10-30 minutes. Moderate
thunderstorms will produce 0.2-0.5" in 10-30 minutes.
WORST CASE SCENARIO: The warm layer of air aloft erodes allowing for
more numerous moderate and strong thunderstorms with the potential to
produce heavy rainfall rates of 0.4-1.0" in 10-30 minutes.
A LOOK AHEAD: We will tack on a few more degrees to high temperatures
on Wednesday and add a little more moisture. With more heat and
moisture to work with there will be a better chance for afternoon
thunderstorms, some of which may contain heavy rainfall. Thursday and
Friday will feature a high likelihood of afternoon and evening
thunderstorms with the potential to produce heavy rainfall that may
result in excessive runoff and flash flooding.
LOCATION
PRIME TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Â
Â
Â
Adams
400 PM TO 800 PM
Trace (40%) to 0.2" (20%) to 0.5" (5%)
NONE
Arapahoe
400 PM TO 800 PM
Trace (40%) to 0.2" (20%) to 0.5" (5%)
NONE
Broomfield
400 PM TO 800 PM
Trace (40%) to 0.2" (20%) to 0.5" (5%)
NONE
Denver
400 PM TO 800 PM
Trace (40%) to 0.2" (20%) to 0.5" (5%)
NONE
Boulder
300 PM TO 800 PM
Trace (60%) to 0.2" (25%) to 0.5" (5%)
NONE
Douglas
300 PM TO 800 PM
Trace (60%) to 0.2" (25%) to 0.5" (5%)
NONE
Jefferson
300 PM TO 800 PM
Trace (60%) to 0.2" (25%) to 0.5" (5%)
NONE
Foothills above 6500ft
Â
Â
Â
Boulder
200 PM TO 800 PM
Trace (80%) to 0.2" (50%) to 0.5" (15%)
LOW
Douglas
200 PM TO 800 PM
Trace (80%) to 0.2" (50%) to 0.5" (15%)
LOW
Jefferson
200 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 Â Â Â F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
3 years, 5 months
Flash Flood Prediction Program
by f2p2@udfcd.org
Time: 710 PM Mon June 28, 2021
Forecaster: Justin Brooks
-------------------------
Internal Message Status
Flash Flood Prediction Program
-------------------------
MESSAGE 1'S WILL BE ALLOWED TO EXPIRE AT 8:00 PM FOR PORTIONS OF THE
DISTRICT
-
Message 1's that have been issued for Adams, Arapahoe, Denver,
Douglas and Jefferson Counties will be allowed to expire at 8pm this
evening as the threat for heavy rainfall has come to an end.
-
Most rain shower activity has cleared out of the District at this
time. Skies will continue to gradually clear out through the overnight
for the plains, with a few lingering scattered light rain showers
still possible towards the foothills. Conditions will generally be
dry, although a few light rain showers could persist through midnight,
favoring areas along the foothills and west of I-25.
-
Overnight lows will drop into the 50's with mild conditions through
the morning. A shift in the overall pattern tomorrow with a chance for
rain showers/isolated thunderstorms in the afternoon which will move
in from the south to north. Tomorrow will also start a warming trend
over the region where we could see temperatures hit 80 degrees for the
first time in several days.
STORM RAINFALL POTENTIAL AND DURATION: Sprinkles to light rain will
produce a trace to 0.1" in 10-30 minutes.
WORST CASE SCENARIO: Light to moderate rain showers have the potential
to produce 0.1-0.3" in 45-60 minutes.
COUNTY
MESSAGE
VALID TIMES
PRIME TIME
Jefferson County
1
Current TO 800 PM
Current TO 800 PM
Douglas County
1
Current TO 800 PM
Current TO 800 PM
Adams County
1
Current TO 800 PM
Current TO 800 PM
Denver County
1
Current TO 800 PM
Current TO 800 PM
DIA
1
Current TO 800 PM
Current TO 800 PM
Arapahoe County
1
Current TO 800 PM
Current TO 800 PM
the City of Aurora
1
Current TO 800 PM
Current TO 800 PM
Arvada
1
Current TO 800 PM
Current TO 800 PM
Wheat Ridge
1
Current TO 800 PM
Current TO 800 PM
Lakewood
1
Current TO 800 PM
Current TO 800 PM
County-specific Quantitative
Precipitation Outlook PRECIPITATION TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Â
Â
Â
Adams
Current TO 1159 PM MON
Trace (10%) to 0.1" (5%) to 0.3" (0%)
NONE
Arapahoe
Current TO 1159 PM MON
Trace (10%) to 0.1" (5%) to 0.3" (0%)
NONE
Boulder
Current TO 1159 PM MON
Trace (10%) to 0.1" (5%) to 0.3" (0%)
NONE
Broomfield
Current TO 1159 PM MON
Trace (10%) to 0.1" (5%) to 0.3" (0%)
NONE
Denver
Current TO 1159 PM MON
Trace (10%) to 0.1" (5%) to 0.3" (0%)
NONE
Douglas
Current TO 1159 PM MON
Trace (10%) to 0.1" (5%) to 0.3" (0%)
NONE
Jefferson
Current TO 1159 PM MON
Trace (10%) to 0.1" (5%) to 0.3" (0%)
NONE
Foothills above 6500ft
Â
Â
Â
Boulder
Current TO 1159 PM MON
Trace (20%) to 0.1" (10%) to 0.3" (5%)
NONE
Douglas
Current TO 1159 PM MON
Trace (20%) to 0.1" (10%) to 0.3" (5%)
NONE
Jefferson
Current TO 1159 PM MON
Trace (20%) to 0.1" (10%) to 0.3" (5%)
NONE
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 Â Â Â F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
3 years, 6 months
Flash Flood Prediction Program
by f2p2@udfcd.org
Time: 426 PM Mon June 28, 2021
Forecaster: Brad Simmons
-------------------------
Internal Message Status
Flash Flood Prediction Program
-------------------------
MESSAGE 1'S CONTINUE VALID FOR PORTIONS OF THE DISTRICT
-
Message 1's continue valid for Adams, Arapahoe, Denver, Douglas and
Jefferson Counties until 8pm this evening, however the threat for
heavy rainfall is diminishing.
-
A gust front moved through the District from NW to SE and generated
a few isolated thunderstorms over eastern areas of the District but
did not produce much additional activity. Now that this gust front has
moved through we are lacking a trigger for new storms and the threat
for thunderstorms is lowering with temperatures in the 60's to lower
70's over the plains.
-
A weak wave to the N may still be able to produce weak to moderate
thunderstorm activity later this afternoon and early evening as it
moves into the District.
STORM RAINFALL POTENTIAL AND DURATION: Rain showers and weak
thunderstorms will produce a trace to 0.2" in 10-30 minutes. Moderate
to strong thunderstorms will have the potential to produce 0.2-0.6" in
10-30 minutes.
WORST CASE SCENARIO: A large or slower moving thunderstorm may result
in up to 1.2" of rain in 45-60 minutes.
COUNTY
MESSAGE
VALID TIMES
PRIME TIME
Jefferson County
1
Current TO 800 PM
245 PM TO 600 PM
Douglas County
1
Current TO 800 PM
245 PM TO 700 PM
Adams County
1
Current TO 800 PM
245 PM TO 700 PM
Denver County
1
Current TO 800 PM
245 PM TO 700 PM
DIA
1
Current TO 800 PM
245 PM TO 700 PM
Arapahoe County
1
Current TO 800 PM
245 PM TO 700 PM
the City of Aurora
1
Current TO 800 PM
245 PM TO 700 PM
Arvada
1
Current TO 800 PM
245 PM TO 700 PM
Wheat Ridge
1
Current TO 800 PM
245 PM TO 700 PM
Lakewood
1
Current TO 800 PM
245 PM TO 700 PM
County-specific Quantitative
Precipitation Outlook PRECIPITATION TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Â
Â
Â
Adams
Current TO 800 PM MON
Trace (60%) to 0.2" (30%) to 0.6" (10%)
ISSUED
Arapahoe
Current TO 800 PM MON
Trace (60%) to 0.2" (30%) to 0.6" (10%)
ISSUED
Boulder
Current TO 800 PM MON
Trace (60%) to 0.2" (30%) to 0.6" (10%)
LOW
Broomfield
Current TO 800 PM MON
Trace (60%) to 0.2" (30%) to 0.6" (10%)
LOW
Denver
Current TO 800 PM MON
Trace (60%) to 0.2" (30%) to 0.6" (10%)
ISSUED
Douglas
Current TO 800 PM MON
Trace (60%) to 0.2" (30%) to 0.6" (10%)
ISSUED
Jefferson
Current TO 800 PM MON
Trace (60%) to 0.2" (30%) to 0.6" (10%)
ISSUED
Foothills above 6500ft
Â
Â
Â
Boulder
Current TO 800 PM MON
Trace (60%) to 0.2" (30%) to 0.6" (10%)
LOW
Douglas
Current TO 800 PM MON
Trace (60%) to 0.2" (30%) to 0.6" (10%)
ISSUED
Jefferson
Current TO 800 PM MON
Trace (60%) to 0.2" (30%) to 0.6" (10%)
ISSUED
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 Â Â Â F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
3 years, 6 months
Flash Flood Prediction Program
by f2p2@udfcd.org
Time: 216 PM Mon June 28, 2021
Forecaster: Brad Simmons
-------------------------
Internal Message Status
Flash Flood Prediction Program
-------------------------
MESSAGE 1'S ISSUED FOR PORTIONS OF THE DISTRICT
-
Message 1's have been issued for Adams, Arapahoe, Denver, Douglas
and Jefferson Counties and will be valid until 8pm this evening.
-
Weak to briefly moderate thunderstorms over the foothills of Boulder
County earlier today has produced a gust front that is pushing SE
through the District and may be a trigger for stronger thunderstorms
to develop later this afternoon. Since this gust front/outflow
boundary has already passed Boulder and Broomfield Counties they are
not included in the Message 1's at this time but may be added later
this afternoon if conditions warrant.
-
Moderate to strong thunderstorms will be capable of producing heavy
rainfall that may lead to excessive runoff and possibly flash
flooding. Best chances for thunderstorms will be over the next
4-5hours.
STORM RAINFALL POTENTIAL AND DURATION: Moderate to strong
thunderstorms will have the potential to produce 0.3-0.8" in 10-30
minutes.
WORST CASE SCENARIO: A large or slower moving thunderstorm may result
in up to 1.5" of rain in 45-60 minutes.
COUNTY
MESSAGE
VALID TIMES
PRIME TIME
Lakewood
1
Current TO 800 PM
245 PM TO 600 PM
Arvada
1
Current TO 800 PM
245 PM TO 600 PM
Wheat Ridge
1
Current TO 800 PM
245 PM TO 600 PM
the City of Aurora
1
Current TO 800 PM
245 PM TO 600 PM
DIA
1
Current TO 800 PM
245 PM TO 600 PM
Arapahoe County
1
Current TO 800 PM
245 PM TO 600 PM
Denver County
1
Current TO 800 PM
245 PM TO 600 PM
Adams County
1
Current TO 800 PM
245 PM TO 600 PM
Douglas County
1
Current TO 800 PM
245 PM TO 600 PM
Jefferson County
1
Current TO 800 PM
245 PM TO 600 PM
County-specific Quantitative
Precipitation Outlook PRECIPITATION TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Â
Â
Â
Adams
Current TO 800 PM MON
0.1" (80%) to 0.4" (60%) to 0.8" (30%)
ISSUED
Arapahoe
Current TO 800 PM MON
0.1" (80%) to 0.4" (60%) to 0.8" (30%)
ISSUED
Boulder
Current TO 800 PM MON
0.1" (60%) to 0.4" (30%) to 0.8" (15%)
MOD
Broomfield
Current TO 800 PM MON
0.1" (50%) to 0.4" (25%) to 0.8" (10%)
MOD
Denver
Current TO 800 PM MON
0.1" (80%) to 0.4" (60%) to 0.8" (30%)
ISSUED
Douglas
Current TO 800 PM MON
0.1" (80%) to 0.4" (60%) to 0.8" (30%)
ISSUED
Jefferson
Current TO 800 PM MON
0.1" (80%) to 0.4" (60%) to 0.8" (30%)
ISSUED
Foothills above 6500ft
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Boulder
Current TO 800 PM MON
0.1" (60%) to 0.4" (30%) to 0.8" (15%)
MOD
Douglas
Current TO 800 PM MON
0.1" (80%) to 0.4" (60%) to 0.8" (30%)
ISSUED
Jefferson
Current TO 800 PM MON
0.1" (80%) to 0.4" (60%) to 0.8" (30%)
ISSUED
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 Â Â Â F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
3 years, 6 months
Flash Flood Prediction Program
by f2p2@udfcd.org
Time: 858 AM Mon June 28, 2021
Forecaster: Brad Simmons
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
CONTINUED UNSEASONABLY COOL WITH LESS NUMEROUS SHOWERS AND
THUNDERSTORMS FAVORING THE FOOTHILLS
-
Temperatures will remain below seasonal averages over the District
today with highs in the 70's over the plains and 60's in the Front
Range foothills. Normal high for Denver today is 87 degrees. Rain
showers and isolated to widely scattered thunderstorms are expected
this afternoon, however the shower and thunderstorm coverage is
expected to be less than previous days as moisture has decreased a bit
from this time yesterday.
-
Rain showers and weak thunderstorms will become possible before
noon, mainly in and near the foothills. Upper level steering winds at
around 15mph from N to S through early afternoon and NW to SE later
this afternoon is expected to keep the majority of the storm activity
over the foothills. Over the plains the best chances for storms will
be along and W of I-25 and S of I-70 with far NE areas of the District
expected to have the lowest chance for storm activity today.
-
Thunderstorm strength this afternoon will hinge upon daytime heating
with weak to moderate thunderstorms currently expected and
temperatures reaching the low to mid 70's. Should temperatures warm
more than anticipated into the upper 70's stronger thunderstorms may
develop and there will be a better chance for heavy rainfall.
STORM RAINFALL POTENTIAL AND DURATION: Rain showers and weak
thunderstorms will produce a trace to 0.2" of rain. Moderate to
briefly strong thunderstorms will have the potential to produce
0.2-0.6" in 10-30 minutes.
WORST CASE SCENARIO: Temperatures warm further than anticipated
resulting in strong thunderstorms with the potential to produce
0.4-1.2" of rain in 10-30 minutes and up to 2.0" in 45-60 minutes.
A LOOK AHEAD: A similar outlook on Tuesday with isolated to widely
scattered afternoon thunderstorms and temperatures in the 70's for
highs. A low threat for heavy rainfall is expected. We add more heat
and moisture into the equation from Wednesday through Friday resulting
in a moderate to high threat for heavy rainfall producing
thunderstorms each day, likely peaking on Friday.
LOCATION
PRIME TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Â
Â
Â
Adams
100 PM TO 1000 PM
0.1" (60%) to 0.3" (30%) to 0.6" (10%)
LOW
Arapahoe
100 PM TO 1000 PM
0.1" (70%) to 0.3" (50%) to 0.6" (20%)
LOW
Broomfield
100 PM TO 1000 PM
0.1" (80%) to 0.3" (60%) to 0.6" (25%)
MOD
Denver
100 PM TO 1000 PM
0.1" (70%) to 0.3" (50%) to 0.6" (20%)
LOW
Boulder
1200 PM TO 1000 PM
0.1" (80%) to 0.3" (60%) to 0.6" (25%)
MOD
Douglas
1200 PM TO 1000 PM
0.1" (80%) to 0.3" (60%) to 0.6" (25%)
MOD
Jefferson
1200 PM TO 1000 PM
0.1" (80%) to 0.3" (60%) to 0.6" (25%)
MOD
Foothills above 6500ft
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Boulder
100 PM TO 1000 PM
0.1" (90%) to 0.3" (70%) to 0.6" (40%)
MOD
Douglas
100 PM TO 1000 PM
0.1" (90%) to 0.3" (70%) to 0.6" (40%)
MOD
Jefferson
100 PM TO 1000 PM
0.1" (90%) to 0.3" (70%) to 0.6" (40%)
MOD
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 Â Â Â F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
3 years, 6 months
Flash Flood Prediction Program
by f2p2@udfcd.org
Time: 825 PM Sun June 27, 2021
Forecaster: Brad Simmons
-------------------------
Internal Message Status
Flash Flood Prediction Program
-------------------------
MESSAGE 1'S WILL BE ALLOWED TO EXPIRE, ADDITIONAL RAIN SHOWERS TO
CONTINUE INTO THE LATE EVENING
-
Message 1's will be allowed to expire at 9:00pm as the threat for
heavy rainfall from thunderstorms has ended for the day.
-
A weak disturbance upstream is expected to produce additional widely
scattered light rain showers through about midnight, likely favoring
areas W of I-25 and over the foothills. Beyond midnight there could be
a few lingering, isolated showers that persist into early Monday
morning. Showers will move briskly from N to S at around 15mph.
Although unlikely, if a weak thunderstorm were to develop it would be
capable of producing brief heavy rainfall.
-
Due to all of the moisture as of late over large areas of the
District it may not take much additional rain to produce runoff and
smaller creeks and streams may be susceptible to higher flows into the
evening.
STORM RAINFALL POTENTIAL AND DURATION: Rainfall rates from light rain
showers will generally range from a trace to 0.2" in 30-60 minutes
with moderate rain showers producing rainfall rates of 0.2-0.5" in
30-60 minutes.
WORST CASE SCENARIO: Weak to moderate thunderstorms are able to
develop with the potential to produce brief heavy rainfall of 0.3-0.9"
in 10-30 minutes.
COUNTY
MESSAGE
VALID TIMES
PRIME TIME
Denver County
1
Current TO 900 PM
Current TO 800 PM MONDAY
Adams County
1
Current TO 900 PM
Current TO 800 PM MONDAY
Douglas County
1
Current TO 900 PM
Current TO 800 PM MONDAY
Broomfield County
1
Current TO 900 PM
Current TO 800 PM MONDAY
Jefferson County
1
Current TO 900 PM
Current TO 800 PM MONDAY
Boulder County
1
Current TO 900 PM
Current TO 800 PM MONDAY
DIA
1
Current TO 900 PM
Current TO 800 PM MONDAY
Arapahoe County
1
Current TO 900 PM
Current TO 800 PM MONDAY
the City of Aurora
1
Current TO 900 PM
Current TO 800 PM MONDAY
Arvada
1
Current TO 900 PM
Current TO 800 PM MONDAY
Wheat Ridge
1
Current TO 900 PM
Current TO 800 PM MONDAY
Lakewood
1
Current TO 900 PM
Current TO 800 PM MONDAY
County-specific Quantitative
Precipitation Outlook PRECIPITATION TIME
60-Minute Rainfall
and % Probability Message
Potential
Plains
Â
Â
Â
Adams
Current TO 400 AM MON
Trace (75%) to 0.2" (50%) to 0.5" (15%)
NONE
Arapahoe
Current TO 400 AM MON
Trace (75%) to 0.2" (50%) to 0.5" (15%)
NONE
Boulder
Current TO 400 AM MON
Trace (75%) to 0.2" (50%) to 0.5" (15%)
NONE
Broomfield
Current TO 400 AM MON
Trace (75%) to 0.2" (50%) to 0.5" (15%)
NONE
Denver
Current TO 400 AM MON
Trace (75%) to 0.2" (50%) to 0.5" (15%)
NONE
Douglas
Current TO 400 AM MON
Trace (75%) to 0.2" (50%) to 0.5" (15%)
NONE
Jefferson
Current TO 400 AM MON
Trace (75%) to 0.2" (50%) to 0.5" (15%)
NONE
Foothills above 6500ft
Â
Â
Â
Boulder
Current TO 400 AM MON
Trace (95%) to 0.2" (60%) to 0.5" (20%)
NONE
Douglas
Current TO 400 AM MON
Trace (95%) to 0.2" (60%) to 0.4" (20%)
NONE
Jefferson
Current TO 400 AM MON
Trace (95%) to 0.2" (60%) to 0.4" (20%)
NONE
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 Â Â Â F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
3 years, 6 months