Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 854 AM Sat May 27, 2023
Forecaster: Laura Smith
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
ANOTHER ROUND OF SLOW-MOVING THUNDERSTORMS EXPECTED THIS AFTERNOON
ACROSS THE DISTRICT
A blocking pattern is in place over the continental US, positioning
southwesterly upper-level flow across Colorado while low level
moisture east of the Continental Divide remains heightened from
yesterday’s storms. This morning will be mostly sunny across the
Front Range Urban Corridor followed by high temperatures in the upper
70s to low 80s, dew points in the upper 40s to low 50s, through the
afternoon and evening. PWAT values between 0.65” to 0.75” are
expected today.
These conditions will support an unstable environment, favorable for
thunderstorm development across the area by the mid to late afternoon.
Forecast soundings reveal bulk shear around 30 kt, which will be
sufficient for multicell clusters and slow storm motions. Heavy rain
may persist for an extended period of time with special emphasis on
areas east of I-25 around the convergence zone. Storms are expected to
dissipate by the late evening hours.
STORM RAINFALL POTENTIAL AND DURATION: Typical thunderstorms will
produce a 0.25” to 0.50” in 10-30 minutes. A strong thunderstorm
could produce 0.50” to 1.00” in 10-30 minutes.
WORST CASE SCENARIO: Anchored or slow-moving thunderstorms have the
potential to produce 1.00”-1.50” in 45-60 minutes.
A LOOK AHEAD: Similar conditions are likely tomorrow as temperatures
reach the upper 70s to low 80s followed by scattered afternoon to
evening thunderstorms, with a potential for severe storms and heavy
rain once again. Looking ahead, the upper-level pattern remains in
place through early next week, with high temperatures around 80°F and
afternoon to evening showers and thunderstorms.
LOCATION
PRIME TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
200 PM TO 1000 PM
0.25" (75%) to 0.5" (50%) to 1" (25%)
HIGH
Arapahoe
200 PM TO 1000 PM
0.25" (75%) to 0.5" (50%) to 1" (25%)
HIGH
Boulder
200 PM TO 1000 PM
0.25" (75%) to 0.5" (50%) to 1" (25%)
HIGH
Broomfield
200 PM TO 1000 PM
0.25" (75%) to 0.5" (50%) to 1" (25%)
HIGH
Denver
200 PM TO 1000 PM
0.25" (75%) to 0.5" (50%) to 1" (25%)
HIGH
Douglas
200 PM TO 1000 PM
0.25" (75%) to 0.5" (50%) to 1" (25%)
HIGH
Jefferson
200 PM TO 1000 PM
0.25" (75%) to 0.5" (50%) to 1" (25%)
HIGH
Foothills above 6500ft
Boulder
100 PM TO 800 PM
0.25" (75%) to 0.5" (50%) to 1" (25%)
HIGH
Douglas
100 PM TO 800 PM
0.25" (75%) to 0.5" (50%) to 1" (25%)
HIGH
Jefferson
100 PM TO 800 PM
0.25" (75%) to 0.5" (50%) to 1" (25%)
HIGH
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, 5 months
Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 905 PM Fri May 26, 2023
Forecaster: Justin Brooks
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
ADDITIONAL STORMS DEVELOPING ALONG FOOTHILLS CURRENTLY RESULTING IN
LOW CHANCE FOR MESSAGE 1'S THIS EVENING
Additional storms have developed along the foothills at this time
and will likely move into the District in the next hour or so. These
storms are much weaker than this afternoon. However, persistent
easterly surface flow, combined with dew points still around 50
degrees, will bring a LOW chance that Message 1’s will have to be
issued this evening.
The best chance for additional storms will be from now until midnight
with skies gradually clearing through the overnight and into Saturday.
The main threat for these storms will likely be a quick 0.5” in
10-30 minutes as storm motions remain fairly quick, between 10-15mph
which will help limit point rainfall amounts. The biggest area of
concern will be along the foothills, where storms are more likely to
anchor in place, resulting in the best chance for brief heavy rain.
Storm chances will taper off after 10pm with a few lingering showers
through midnight.
Overnight will be mild and dry, with lows dropping into the upper
40’s to around 50 on the plains, with low to mid 40’s along the
foothills.
STORM RAINFALL POTENTIAL AND DURATION: Rain showers will produce
rainfall amounts of TR-0.2” in 10-30 minutes. Weak to moderate
thunderstorms will have the potential to produce rainfall rates of
0.2-
0.5” in 10-30 minutes.
WORST CASE SCENARIO: A moderate to strong thunderstorm, or an anchored
thunderstorm has the potential to produce heavy rainfall of up to
0.8” in 45-60 minutes.
A LOOK AHEAD: Not much change in the overall pattern as tomorrow will
bring another threat of severe weather for portions of northeastern
Colorado, which could include areas east and up to the I-25 corridor.
The best chance for storms will once again be during peak daytime
heating in the afternoon and early evening. Expect at least a moderate
if not high chance for Messages to be issued tomorrow as well.
LOCATION
PRIME TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
Current TO 1159 PM FRI
Trace (60%) to 0.2" (20%) to 0.5" (10%)
LOW
Arapahoe
Current TO 1159 PM FRI
Trace (60%) to 0.2" (20%) to 0.5" (10%)
LOW
Boulder
Current TO 1159 PM FRI
Trace (60%) to 0.2" (20%) to 0.5" (10%)
LOW
Broomfield
Current TO 1159 PM FRI
Trace (60%) to 0.2" (20%) to 0.5" (10%)
LOW
Denver
Current TO 1159 PM FRI
Trace (60%) to 0.2" (20%) to 0.5" (10%)
LOW
Douglas
Current TO 1159 PM FRI
Trace (60%) to 0.2" (20%) to 0.5" (10%)
LOW
Jefferson
Current TO 1159 PM FRI
Trace (60%) to 0.2" (20%) to 0.5" (10%)
LOW
Foothills above 6500ft
Boulder
Current TO 1159 PM FRI
Trace (80%) to 0.2" (40%) to 0.5" (20%)
LOW
Douglas
Current TO 1159 PM FRI
Trace (80%) to 0.2" (40%) to 0.5" (20%)
LOW
Jefferson
Current TO 1159 PM FRI
Trace (80%) to 0.2" (40%) to 0.5" (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, 5 months
Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 548 PM Fri May 26, 2023
Forecaster: Brad Simmons
-------------------------
Internal Message Status
Flash Flood Prediction Program
-------------------------
MESSAGE 1'S HAVE BEEN RESCINDED/HEAVY RAINFALL THREAT HAS ENDED FOR
TODAY
Message 1’s have been rescinded (Message 4 issued) as the threat
for heavy rainfall has ended for the day.
Thunderstorm activity has pushed east of the District and a more
stable air mass is now in place and strong thunderstorms are no longer
expected. There could be a few additional rain showers and possibly a
very isolated weak thunderstorm this evening, but additional shower
activity will only produce minor additional rainfall amounts. Best
chances for additional showers will be over the foothills into the
evening with dry conditions ahead of midnight.
A down-tick in thunderstorm activity is expected on Saturday but there
will still be afternoon thunderstorms with the potential to produce
heavy rainfall but the areal coverage of storms will likely be less
than today.
STORM RAINFALL POTENTIAL AND DURATION: Rain showers and possibly a
weak thunderstorm will produce rainfall amounts of trace to 0.2" in
10-30 minutes.
WORST CASE SCENARIO: A very isolated moderate thunderstorm is able to
develop with the potential to produce rainfall rates of 0.2-0.6" 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 1100 PM FRI
Trace (20%) to 0.1" (10%) to 0.2" (5%)
NONE
Arapahoe
Current TO 1100 PM FRI
Trace (20%) to 0.1" (10%) to 0.2" (5%)
NONE
Boulder
Current TO 1100 PM FRI
Trace (20%) to 0.1" (10%) to 0.2" (5%)
NONE
Broomfield
Current TO 1100 PM FRI
Trace (20%) to 0.1" (10%) to 0.2" (5%)
NONE
Denver
Current TO 1100 PM FRI
Trace (20%) to 0.1" (10%) to 0.2" (5%)
NONE
Douglas
Current TO 1100 PM FRI
Trace (20%) to 0.1" (10%) to 0.2" (5%)
NONE
Jefferson
Current TO 1100 PM FRI
Trace (20%) to 0.1" (10%) to 0.2" (5%)
NONE
Foothills above 6500ft
Boulder
Current TO 1100 PM FRI
Trace (40%) to 0.1" (20%) to 0.2" (10%)
NONE
Douglas
Current TO 1100 PM FRI
Trace (40%) to 0.1" (20%) to 0.2" (10%)
NONE
Jefferson
Current TO 1100 PM FRI
Trace (40%) to 0.1" (20%) to 0.2" (10%)
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, 5 months
Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 1244 PM Fri May 26, 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 9:00pm this evening.
Daytime heating is already starting to generate thunderstorm activity
over the foothills and storms will begin to move over the plains over
the next few hours. Surface moisture is abundant with dew points
currently in the lower 50’s which will be fuel for thunderstorms
this afternoon. Stronger thunderstorms will be capable of producing
heavy rainfall that may lead to excessive runoff and possibly flash
flooding. Strong thunderstorms will also contain large hail, frequent
cloud-to-ground lightning and gusty winds.
1-2 rounds of thunderstorms are expected through the course of the
afternoon. Typical thunderstorms will move from SW to NE at around
15mph but stronger storms may move more slowly or erratically. After 8
or 9pm the thunderstorm activity is expected to have pushed to the
east of the District with possibly a few lingering lighter rain
showers persisting into the late evening.
STORM RAINFALL POTENTIAL AND DURATION: Moderate to strong
thunderstorms will have the potential to produce rainfall rates of
0.4-1.0” in 10-30 minutes.
WORST CASE SCENARIO: A slower moving strong thunderstorm or a large
thunderstorm complex may result in up to 1.8” of rain in 45-60
minutes.
COUNTY
MESSAGE
VALID TIMES
PRIME TIME
Lakewood
1
1230 PM TO 900 PM
130 PM TO 800 PM
Wheat Ridge
1
1230 PM TO 900 PM
130 PM TO 800 PM
the City of Aurora
1
1230 PM TO 900 PM
130 PM TO 800 PM
DIA
1
1230 PM TO 900 PM
130 PM TO 800 PM
Arapahoe County
1
1230 PM TO 900 PM
130 PM TO 800 PM
Denver County
1
1230 PM TO 900 PM
130 PM TO 800 PM
Adams County
1
1230 PM TO 900 PM
130 PM TO 800 PM
Douglas County
1
1230 PM TO 900 PM
130 PM TO 800 PM
Broomfield County
1
1230 PM TO 900 PM
130 PM TO 800 PM
Jefferson County
1
1230 PM TO 900 PM
130 PM TO 800 PM
Boulder County
1
1230 PM TO 900 PM
130 PM TO 800 PM
Arvada
1
1230 PM TO 900 PM
130 PM TO 800 PM
County-specific Quantitative
Precipitation Outlook PRECIPITATION TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
100 PM TO 900 PM
0.1" (90%) to 0.5" (60%) to 1" (30%)
ISSUED
Arapahoe
100 PM TO 900 PM
0.1" (90%) to 0.5" (60%) to 1" (30%)
ISSUED
Boulder
100 PM TO 900 PM
0.1" (90%) to 0.5" (50%) to 1" (20%)
ISSUED
Broomfield
100 PM TO 900 PM
0.1" (90%) to 0.5" (50%) to 1" (20%)
ISSUED
Denver
100 PM TO 900 PM
0.1" (90%) to 0.5" (55%) to 1" (20%)
ISSUED
Douglas
100 PM TO 900 PM
0.1" (90%) to 0.5" (60%) to 1" (30%)
ISSUED
Jefferson
100 PM TO 900 PM
0.1" (90%) to 0.5" (50%) to 1" (20%)
ISSUED
Foothills above 6500ft
Boulder
Current TO 900 PM FRI
0.1" (95%) to 0.5" (65%) to 1" (30%)
ISSUED
Douglas
Current TO 900 PM FRI
0.1" (95%) to 0.5" (65%) to 1" (30%)
ISSUED
Jefferson
Current TO 900 PM FRI
0.1" (95%) to 0.5" (65%) to 1" (30%)
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, 5 months
Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 846 AM Fri May 26, 2023
Forecaster: Laura Smith
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
ANOTHER ROUND OF SLOW-MOVING THUNDERSTORMS EXPECTED THIS AFTERNOON
ACROSS THE DISTRICT
A blocking pattern is in place over the continental US, positioning
southwesterly upper-level flow across Colorado while low level
moisture east of the Continental Divide remains heightened. High
temperatures will reach the mid to upper 70s, dew points in the upper
40s to low 50s, through the afternoon and evening.
These conditions will support an unstable environment, favorable for
thunderstorm development across the area by the mid to late afternoon.
Forecast soundings reveal weak wind shear profiles, resulting in west
to east slow-moving multicell clusters. Heavy rain may persist for an
extended period of time with special emphasis on areas east of I-25
around the convergence zone. Storms are expected to dissipate by the
late evening hours.
STORM RAINFALL POTENTIAL AND DURATION: Typical thunderstorms will
produce a 0.25” to 0.75” in 10-30 minutes. A strong thunderstorm
could produce 0.75” to 1.00” in 10-30 minutes.
WORST CASE SCENARIO: Anchored or training thunderstorms have the
potential to produce 1.00”-1.60” in 30-60 minutes.
A LOOK AHEAD: Similar conditions are likely tomorrow as temperatures
reach the upper 70s to low 80s followed by widely scattered late
afternoon to evening thunderstorms, with a potential for heavy rain
once again. Looking ahead, the upper-level pattern remains in place
through the weekend supporting high temperatures around 80°F and
afternoon to evening showers and thunderstorms.
LOCATION
PRIME TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
300 PM TO 700 PM
0.1" (90%) to 0.5" (50%) to 1" (15%)
HIGH
Arapahoe
300 PM TO 700 PM
0.1" (90%) to 0.5" (50%) to 1" (15%)
HIGH
Boulder
300 PM TO 700 PM
0.1" (90%) to 0.5" (50%) to 1" (15%)
HIGH
Broomfield
300 PM TO 700 PM
0.1" (90%) to 0.5" (50%) to 1" (15%)
HIGH
Denver
300 PM TO 700 PM
0.1" (90%) to 0.5" (50%) to 1" (15%)
HIGH
Douglas
300 PM TO 700 PM
0.1" (90%) to 0.5" (50%) to 1" (15%)
HIGH
Jefferson
300 PM TO 700 PM
0.1" (90%) to 0.5" (50%) to 1" (15%)
HIGH
Foothills above 6500ft
Boulder
200 PM TO 600 PM
0.1" (90%) to 0.5" (50%) to 1" (15%)
HIGH
Douglas
200 PM TO 600 PM
0.1" (90%) to 0.5" (50%) to 1" (15%)
HIGH
Jefferson
200 PM TO 600 PM
0.1" (90%) to 0.5" (50%) to 1" (15%)
HIGH
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, 5 months
Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 825 PM Thu May 25, 2023
Forecaster: Brad Simmons
-------------------------
Internal Message Status
Flash Flood Prediction Program
-------------------------
MESSAGE 1'S WILL BE ALLOWED TO EXPIRE AT 9:30 PM
Message 1’s will be allowed to expire as the threat for heavy
rainfall has ended for the day.
Thunderstorm activity has moved east of the District and with cooling
temperatures no additional thunderstorms are expected this evening.
Generally dry conditions will persist into Friday morning for many
areas but an isolated rain shower cannot be completely ruled out over
the next few hours with completely dry conditions ahead of midnight.
Any additional shower activity will favor the foothills.
Surface moisture will remain in place tomorrow and another round of
afternoon thunderstorms are expected with stronger storms capable of
producing brief heavy rainfall and large hail.
STORM RAINFALL POTENTIAL AND DURATION: Most areas will trend on the
dry side with isolated rain showers producing a trace to 0.1” of
rain.
COUNTY
MESSAGE
VALID TIMES
PRIME TIME
Boulder County
1
230 PM TO 930 PM
330 PM TO 830 PM
Jefferson County
1
230 PM TO 930 PM
330 PM TO 830 PM
Broomfield County
1
230 PM TO 930 PM
330 PM TO 830 PM
Douglas County
1
230 PM TO 930 PM
330 PM TO 830 PM
Adams County
1
230 PM TO 930 PM
330 PM TO 830 PM
Denver County
1
230 PM TO 930 PM
330 PM TO 830 PM
DIA
1
230 PM TO 930 PM
330 PM TO 830 PM
Arapahoe County
1
230 PM TO 930 PM
330 PM TO 830 PM
the City of Aurora
1
230 PM TO 930 PM
330 PM TO 830 PM
Arvada
1
230 PM TO 930 PM
330 PM TO 830 PM
Wheat Ridge
1
230 PM TO 930 PM
330 PM TO 830 PM
Lakewood
1
230 PM TO 930 PM
330 PM TO 830 PM
County-specific Quantitative
Precipitation Outlook PRECIPITATION TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
Current TO 1100 PM THU
Trace (15%) to 0.05" (10%) to 0.1" (5%)
ISSUED
Arapahoe
Current TO 1100 PM THU
Trace (15%) to 0.05" (10%) to 0.1" (5%)
ISSUED
Boulder
Current TO 1100 PM THU
Trace (20%) to 0.05" (10%) to 0.1" (5%)
ISSUED
Broomfield
Current TO 1100 PM THU
Trace (15%) to 0.05" (10%) to 0.1" (5%)
ISSUED
Denver
Current TO 1100 PM THU
Trace (15%) to 0.05" (10%) to 0.1" (5%)
ISSUED
Douglas
Current TO 1100 PM THU
Trace (20%) to 0.05" (10%) to 0.1" (5%)
ISSUED
Jefferson
Current TO 1100 PM THU
Trace (20%) to 0.05" (10%) to 0.1" (5%)
ISSUED
Foothills above 6500ft
Boulder
Current TO 1100 PM THU
Trace (30%) to 0.05" (15%) to 0.1" (5%)
ISSUED
Douglas
Current TO 1100 PM THU
Trace (30%) to 0.05" (15%) to 0.1" (5%)
ISSUED
Jefferson
Current TO 1100 PM THU
Trace (30%) to 0.05" (15%) to 0.1" (5%)
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, 5 months
Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 230 PM Thu May 25, 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 9:30pm.
Thunderstorms are expected to develop over the next few hours and move
through the District into the evening. Elevated surface moisture
levels with dew points in the upper 40’s to around 50 will result in
thunderstorms that develop today having the potential to produce brief
heavy rainfall that may result in excessive runoff and possibly flash
flooding. Strong thunderstorms may also contain hail and gusty winds.
Generally, one round of thunderstorms is expected but some areas may
experience a couple of rounds of storms.
After 9:30pm the thunderstorm activity is expected to have moved east
of the District with additional lighter rain showers remaining
possible until around midnight.
STORM RAINFALL POTENTIAL AND DURATION: Moderate to strong
thunderstorms will have the potential to produce rainfall rates of
0.4-1.0” in 10-30 minutes.
WORST CASE SCENARIO: A slow moving strong thunderstorm or a large
thunderstorm may result in up to 1.8” of rain in 45-60 minutes.
COUNTY
MESSAGE
VALID TIMES
PRIME TIME
Lakewood
1
230 PM TO 930 PM
330 PM TO 830 PM
Wheat Ridge
1
230 PM TO 930 PM
330 PM TO 830 PM
Arvada
1
230 PM TO 930 PM
330 PM TO 830 PM
the City of Aurora
1
230 PM TO 930 PM
330 PM TO 830 PM
Arapahoe County
1
230 PM TO 930 PM
330 PM TO 830 PM
Denver County
1
230 PM TO 930 PM
330 PM TO 830 PM
DIA
1
230 PM TO 930 PM
330 PM TO 830 PM
Adams County
1
230 PM TO 930 PM
330 PM TO 830 PM
Douglas County
1
230 PM TO 930 PM
330 PM TO 830 PM
Broomfield County
1
230 PM TO 930 PM
330 PM TO 830 PM
Jefferson County
1
230 PM TO 930 PM
330 PM TO 830 PM
Boulder County
1
230 PM TO 930 PM
330 PM TO 830 PM
County-specific Quantitative
Precipitation Outlook PRECIPITATION TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
300 PM TO 930 PM
0.1" (85%) to 0.4" (50%) to 1" (20%)
ISSUED
Arapahoe
300 PM TO 930 PM
0.1" (90%) to 0.4" (60%) to 1" (30%)
ISSUED
Boulder
300 PM TO 930 PM
0.1" (85%) to 0.4" (50%) to 1" (20%)
ISSUED
Broomfield
300 PM TO 930 PM
0.1" (85%) to 0.4" (50%) to 1" (20%)
ISSUED
Denver
300 PM TO 930 PM
0.1" (85%) to 0.4" (50%) to 1" (20%)
ISSUED
Douglas
300 PM TO 930 PM
0.1" (90%) to 0.4" (60%) to 1" (30%)
ISSUED
Jefferson
300 PM TO 930 PM
0.1" (85%) to 0.4" (50%) to 1" (20%)
ISSUED
Foothills above 6500ft
Boulder
Current TO 930 PM THU
0.1" (90%) to 0.4" (60%) to 1" (30%)
ISSUED
Douglas
Current TO 930 PM THU
0.1" (90%) to 0.4" (60%) to 1" (30%)
ISSUED
Jefferson
Current TO 930 PM THU
0.1" (90%) to 0.4" (60%) to 1" (30%)
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, 5 months
Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 829 AM Thu May 25, 2023
Forecaster: Laura Smith
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
ANOTHER ROUND OF SLOW-MOVING THUNDERSTORMS EXPECTED THIS AFTERNOON
ACROSS THE DISTRICT
A blocking pattern is in place over the continental US, positioning
southwesterly upper-level flow across Colorado while low level
moisture east of the Continental Divide remains heightened from
yesterday's storms. High temperatures will reach the upper 70s to low
80s, dew points in the mid 40s to around 50°F, through the afternoon
and evening.
These conditions will support an unstable environment, favorable for
thunderstorm development across the area by the mid to late afternoon.
Forecast soundings reveal bulk shear around 30 kt, which will be
sufficient for multicell clusters and slow southwesterly storm
motions. Heavy rain may persist for an extended period of time with
special emphasis on areas east of I-25 around the convergence zone.
Storms are expected to dissipate by the late evening hours.
STORM RAINFALL POTENTIAL AND DURATION: Typical thunderstorms will
produce a 0.25” to 0.75” in 10-30 minutes. A strong thunderstorm
could produce 0.75” to 1.00” in 10-30 minutes.
WORST CASE SCENARIO: Anchored or training thunderstorms have the
potential to produce 1.00”-1.75” in 30-60 minutes.
A LOOK AHEAD: Similar conditions are likely tomorrow as temperatures
reach the upper 70s to low 80s followed by widely scattered afternoon
to evening thunderstorms, with a potential for heavy rain once again.
Looking ahead, the upper-level pattern remains in place through the
weekend supporting high temperatures around 80°F and afternoon to
evening showers and thunderstorms.
LOCATION
PRIME TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
400 PM TO 1000 PM
0.25" (75%) to 0.5" (50%) to 1" (25%)
HIGH
Arapahoe
400 PM TO 1000 PM
0.25" (90%) to 0.5" (60%) to 1" (25%)
HIGH
Boulder
400 PM TO 1000 PM
0.25" (75%) to 0.5" (50%) to 1" (15%)
HIGH
Broomfield
400 PM TO 1000 PM
0.25" (75%) to 0.5" (50%) to 1" (15%)
HIGH
Denver
400 PM TO 1000 PM
0.25" (75%) to 0.5" (50%) to 1" (25%)
HIGH
Douglas
400 PM TO 1000 PM
0.25" (90%) to 0.5" (60%) to 1" (25%)
HIGH
Jefferson
400 PM TO 1000 PM
0.25" (75%) to 0.5" (50%) to 1" (15%)
HIGH
Foothills above 6500ft
Boulder
300 PM TO 900 PM
0.25" (75%) to 0.5" (50%) to 1" (15%)
HIGH
Douglas
300 PM TO 900 PM
0.25" (90%) to 0.5" (60%) to 1" (25%)
HIGH
Jefferson
300 PM TO 900 PM
0.25" (90%) to 0.5" (60%) to 1" (25%)
HIGH
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, 5 months
Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 652 PM Wed May 24, 2023
Forecaster: Brad Simmons
-------------------------
Internal Message Status
Flash Flood Prediction Program
-------------------------
MESSAGE 1'S WILL BE ALLOWED TO EXPIRE AT 8:00 PM
Message 1’s will be allowed to expire at 8:00pm as the threat for
heavy rainfall has ended. Cooler temperatures behind the initial wave
of thunderstorms has lowered temperatures in to the 60’s and the
atmosphere has stabilized.
There are a few lingering rain showers lurking to the W of the
District that may pass through this evening but most areas will trend
on the drier side from this point forward into the evening. Best
chances for an additional light rain shower will be W of I-25 in or
near the foothills. Dry conditions are expected all areas by around
10:00pm.
There is some great news though as the SW flow aloft behind the upper
level disturbance has helped to scour out much of the smoke/haze and
air quality has improved significantly from earlier today and this
trend of better air quality will continue into tomorrow.
Lingering moisture and another upper level disturbance will result in
afternoon thunderstorms on Thursday afternoon and the stronger storms
will be capable of producing heavy rainfall which may result in
another Message 1 day across the District if surface moisture remains
elevated. Should surface moisture decrease Message 1's will be less
likely tomorrow.
STORM RAINFALL POTENTIAL AND DURATION: Any additional isolated rain
showers will only produce a trace to 0.10” of rainfall in areas that
receive shower activity. Most areas will be dry from this point
forward.
WORST CASE SCENARIO: Should a weak thunderstorm be able to develop
rainfall rates of 0.1-0.3" in 10-30 minutes will be possible.
COUNTY
MESSAGE
VALID TIMES
PRIME TIME
Boulder County
1
1200 PM TO 800 PM
100 PM TO 700 PM
Jefferson County
1
1200 PM TO 800 PM
100 PM TO 700 PM
Broomfield County
1
1200 PM TO 800 PM
100 PM TO 700 PM
Douglas County
1
1200 PM TO 800 PM
100 PM TO 700 PM
Adams County
1
1200 PM TO 800 PM
100 PM TO 700 PM
Denver County
1
1200 PM TO 800 PM
100 PM TO 700 PM
DIA
1
1200 PM TO 800 PM
100 PM TO 700 PM
Arapahoe County
1
1200 PM TO 800 PM
100 PM TO 700 PM
the City of Aurora
1
1200 PM TO 800 PM
100 PM TO 700 PM
Arvada
1
1200 PM TO 800 PM
100 PM TO 700 PM
Wheat Ridge
1
1200 PM TO 800 PM
100 PM TO 700 PM
Lakewood
1
1200 PM TO 800 PM
100 PM TO 700 PM
County-specific Quantitative
Precipitation Outlook PRECIPITATION TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
Current TO 1000 PM WED
Trace (25%) to 0.05" (15%) to 0.1" (5%)
ISSUED
Arapahoe
Current TO 1000 PM WED
Trace (25%) to 0.05" (15%) to 0.1" (5%)
ISSUED
Boulder
Current TO 1000 PM WED
Trace (40%) to 0.05" (20%) to 0.1" (10%)
ISSUED
Broomfield
Current TO 1000 PM WED
Trace (30%) to 0.05" (20%) to 0.1" (5%)
ISSUED
Denver
Current TO 1000 PM WED
Trace (25%) to 0.05" (15%) to 0.1" (5%)
ISSUED
Douglas
Current TO 1000 PM WED
Trace (25%) to 0.05" (15%) to 0.1" (5%)
ISSUED
Jefferson
Current TO 1000 PM WED
Trace (40%) to 0.05" (20%) to 0.1" (10%)
ISSUED
Foothills above 6500ft
Boulder
Current TO 1000 PM WED
Trace (60%) to 0.05" (30%) to 0.1" (15%)
ISSUED
Douglas
Current TO 1000 PM WED
Trace (30%) to 0.05" (20%) to 0.1" (10%)
ISSUED
Jefferson
Current TO 1000 PM WED
Trace (60%) to 0.05" (30%) to 0.1" (15%)
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, 5 months
Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 410 PM Wed May 24, 2023
Forecaster: Brad Simmons
-------------------------
Internal Message Status
Flash Flood Prediction Program
-------------------------
MESSAGE 1'S CONTINUE VALID/CHANCES FOR THUNDERSTORMS DIMINISHING
Message 1’s continue valid until 8:00pm but the threat for
thunderstorms has greatly diminished behind the initial round of
strong storms. Cooler temperatures in the 50’s to lower 60’s are
responsible for a much lower thunderstorm threat as the atmosphere has
stabilized.
Additional rain showers may re-develop into the evening, but the
thunderstorm threat is very low, however, should a thunderstorm be
able to develop brief heavy rainfall is possible as moisture levels
remain high.
Message 1’s are expected to be allowed to expire at 8:00pm this
evening.
STORM RAINFALL POTENTIAL AND DURATION: Rain showers will produce a
trace to 0.1” of rain. Weak to moderate thunderstorms will have the
potential to produce 0.1-0.4” in 10-30 minutes.
WORST CASE SCENARIO: A strong thunderstorm is able to develop in a
cool air mass with the potential to produce 0.4-1.2” in 10-30
minutes.
COUNTY
MESSAGE
VALID TIMES
PRIME TIME
Jefferson County
1
1200 PM TO 800 PM
100 PM TO 700 PM
Boulder County
1
1200 PM TO 800 PM
100 PM TO 700 PM
the City of Aurora
1
1200 PM TO 800 PM
100 PM TO 700 PM
Arapahoe County
1
1200 PM TO 800 PM
100 PM TO 700 PM
DIA
1
1200 PM TO 800 PM
100 PM TO 700 PM
Denver County
1
1200 PM TO 800 PM
100 PM TO 700 PM
Adams County
1
1200 PM TO 800 PM
100 PM TO 700 PM
Douglas County
1
1200 PM TO 800 PM
100 PM TO 700 PM
Broomfield County
1
1200 PM TO 800 PM
100 PM TO 700 PM
Lakewood
1
1200 PM TO 800 PM
100 PM TO 700 PM
Wheat Ridge
1
1200 PM TO 800 PM
100 PM TO 700 PM
Arvada
1
1200 PM TO 800 PM
100 PM TO 700 PM
County-specific Quantitative
Precipitation Outlook PRECIPITATION TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
Current TO 800 PM WED
0.01" (50%) to 0.2" (25%) to 0.4" (10%)
ISSUED
Arapahoe
Current TO 800 PM WED
0.01" (50%) to 0.2" (25%) to 0.4" (10%)
ISSUED
Boulder
Current TO 800 PM WED
0.01" (50%) to 0.2" (25%) to 0.4" (10%)
ISSUED
Broomfield
Current TO 800 PM WED
0.01" (50%) to 0.2" (25%) to 0.4" (10%)
ISSUED
Denver
Current TO 800 PM WED
0.01" (50%) to 0.2" (25%) to 0.4" (10%)
ISSUED
Douglas
Current TO 800 PM WED
0.01" (50%) to 0.2" (25%) to 0.4" (10%)
ISSUED
Jefferson
Current TO 800 PM WED
0.01" (50%) to 0.2" (25%) to 0.4" (10%)
ISSUED
Foothills above 6500ft
Boulder
Current TO 800 PM WED
0.01" (60%) to 0.2" (30%) to 0.4" (15%)
ISSUED
Douglas
Current TO 800 PM WED
0.01" (60%) to 0.2" (30%) to 0.4" (15%)
ISSUED
Jefferson
Current TO 800 PM WED
0.01" (60%) to 0.2" (30%) to 0.4" (15%)
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, 5 months