Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 939 AM Mon August 5, 2024
Forecaster: Tim Tonge
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
Increasing chance of showers/thunderstorms, hot
Analysis of satellite imagery this morning shows a large plume of
moisture that has draped itself across the entire state of Colorado as
the ridge begins to break down. As a result, precipitable water values
in the 1.00"-1.10" range are present across the District today.
Dewpoints will be in the mid 40s this afternoon, indicating that a
large portion of available moisture is already in the upper atmosphere
rather than at the surface, and all it needs will be proper forcing to
trigger a potential message issuance day.
That forcing arrives from a shortwave that is currently over the San
Juan mountains. This disturbance will travel northeast over the course
of the day, sparking the first round of showers and thunderstorms in
the high country west of the District in the early/mid afternoon.
These storms will then move east/northeast into the District in the
following hours. With abundant moisture to work with, storms today
will be capable of producing heavy localized rainfall, hail, and gusty
outflow winds up to 50mph.
Storm coverage will favor higher elevations as well as the southern
portion of the District (mainly Douglas and southern Jefferson
counties), and has the potential to linger through the evening and
into the early hours of Tuesday.
STORM RAINFALL POTENTIAL AND DURATION: Typical showers and
thunderstorms will produce 0.10"-0.30" total in 10-30 minutes.
Stronger or slower moving thunderstorms will produce 0.30"-0.80" total
in 10-30 minutes.
WORST CASE SCENARIO: A slow-moving/stationary thunderstorm, or
training of thunderstorms along a boundary, may produce 1.50"-1.75" in
30-60 minutes.
A LOOK AHEAD: Similar message issuance potential tomorrow as the
overall setup of the atmosphere does not change much over the next 36
hours. Slightly warmer and drier Wednesday. Growing confidence in the
arrival of a cold front Thursday that will drop temps into the 70s and
deliver a large influx in moisture. Likely moderate/high chance of
message issuance Thursday and Friday.
LOCATION
PRIME TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
300 PM TO 1200 AM TUE
0.1" (50%) to 0.3" (30%) to 0.8" (10%)
LOW
Arapahoe
300 PM TO 1200 AM TUE
0.1" (50%) to 0.3" (30%) to 0.8" (10%)
LOW
Boulder
300 PM TO 1200 AM TUE
0.1" (50%) to 0.3" (30%) to 0.8" (10%)
LOW
Broomfield
300 PM TO 1200 AM TUE
0.1" (50%) to 0.3" (30%) to 0.8" (10%)
LOW
Denver
300 PM TO 1200 AM TUE
0.1" (50%) to 0.3" (30%) to 0.8" (10%)
LOW
Douglas
300 PM TO 1200 AM TUE
0.1" (60%) to 0.4" (40%) to 0.8" (20%)
MOD
Jefferson
300 PM TO 1200 AM TUE
0.1" (60%) to 0.4" (40%) to 0.8" (20%)
MOD
Foothills above 6500ft
Boulder
200 PM TO 1200 AM TUE
0.1" (60%) to 0.4" (40%) to 0.8" (20%)
MOD
Douglas
200 PM TO 1200 AM TUE
0.1" (60%) to 0.4" (40%) to 0.8" (20%)
MOD
Jefferson
200 PM TO 1200 AM TUE
0.1" (60%) to 0.4" (40%) 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]
4 months, 3 weeks
Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 955 AM Sun August 4, 2024
Forecaster: Justin Brooks
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
Hot, isolated late afternoon showers and thunderstorms
Monsoonal moisture is beginning to make its way into Colorado,
though most of it will stay contained west of the Continental Divide
today. Precipitable water (PWAT) values across the District have
returned to normal early August values (~0.75"), but near triple-digit
temperatures and minimal atmospheric forcing will create isolated
coverage of storms that are more likely to produce gusty outflow winds
and lightning than significant rainfall.
Storms will begin to fire in the high country west of the District in
the early afternoon, and make their way into the foothills and urban
corridor by mid afternoon. Storms today will likely favor the Palmer
Divide south of the District and plains to the east, however with the
relative proximity of these storms and the potential for outflow
boundary-driven storm initiation, the chance for message issuance will
be LOW today. Mainly for a quick 0.50" in 10-20 minutes from an
anchored storm rather than any long-lasting rainfall.
Overnight will start to clear out with mild and dry conditions
expected through Monday morning. Temperatures will drop into the mid
to upper 60s on the plains with low 60s along the foothills.
STORM RAINFALL POTENTIAL AND DURATION: Typical showers and
thunderstorms will be capable of producing Trace-0.25" total in 10-30
minutes. Moderate to strong thunderstorms will be capable of producing
0.25-0.50" total in 10-30 minutes.
WORST CASE SCENARIO: A strong/slow moving thunderstorm, or training of
thunderstorms may produce 1.00" of rain in 30-60 minutes.
A LOOK AHEAD: Monsoonal moisture will spill over the Continental
Divide by tomorrow, and southwesterly flow aloft will continuously
deliver available moisture to Colorado for the entirety of the work
week. Rainfall chances will likely be >50% each day of the work week;
Wednesday appears to have the lowest chances of the week as of now. A
strong cold front will drop temperatures Thursday.
LOCATION
PRIME TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
300 PM TO 1100 PM
Trace (30%) to 0.25" (20%) to 0.5" (10%)
LOW
Arapahoe
300 PM TO 1100 PM
Trace (30%) to 0.25" (20%) to 0.5" (10%)
LOW
Boulder
300 PM TO 1100 PM
Trace (30%) to 0.25" (20%) to 0.5" (10%)
LOW
Broomfield
300 PM TO 1100 PM
Trace (30%) to 0.25" (20%) to 0.5" (10%)
LOW
Denver
300 PM TO 1100 PM
Trace (30%) to 0.25" (20%) to 0.5" (10%)
LOW
Douglas
300 PM TO 1100 PM
Trace (30%) to 0.25" (20%) to 0.5" (10%)
LOW
Jefferson
300 PM TO 1100 PM
Trace (30%) to 0.25" (20%) to 0.5" (10%)
LOW
Foothills above 6500ft
Boulder
300 PM TO 1100 PM
Trace (40%) to 0.25" (25%) to 0.5" (15%)
LOW
Douglas
300 PM TO 1100 PM
Trace (40%) to 0.25" (25%) to 0.5" (15%)
LOW
Jefferson
300 PM TO 1100 PM
Trace (40%) to 0.25" (25%) 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]
4 months, 3 weeks
Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 937 AM Sat August 3, 2024
Forecaster: Justin Brooks
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
A Hot, Hazy & Dry Day Today
A high-pressure still churns over the Four Corners region leading to
continued hazy conditions this morning. This high-pressure ridge will
slowly start to move eastward today bringing hot and dry conditions
across the region throughout the day and evening. Temperatures will
increase into the upper 90s this afternoon with hazy skies continuing
into the evening hours. Minimal cloud cover today under mostly sunny
skies. Temperatures overnight will drop into the upper 60s on the
plains with low to mid 60s along the foothills.
STORM RAINFALL POTENTIAL AND DURATION: No precipitation is expected
today or this evening.
A LOOK AHEAD: A shift in the upper-level flow Sunday will usher in
some monsoonal moisture into the region bringing a better chance for
afternoon and evening showers/thunderstorms. The high-pressure ridge
stalls out over the Central US this week, keeping monsoonal moisture
in place leading to good chances for afternoon and evening
showers/thunderstorms Monday and Tuesday. This uptick in moisture
during the week will likely result in a chance for moderate to heavy
rainfall from Monday through Friday.
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
4 months, 3 weeks
Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 935 AM Fri August 2, 2024
Forecaster: Justin Brooks
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
Hot & hazy today with a slight chance for isolated afternoon
showers/thunderstorms.
High-pressure still prevails over the Four Corners region today
leading to continued hazy conditions this morning. Temperatures will
increase into the upper 90s this afternoon with hazy skies continuing
into the evening hours.
A slight chance for isolated afternoon showers/thunderstorms today
with the best chance for any storm activity within the District
between 1-8pm. Initial storm development will be along the Continental
Divide by midday, moving into the foothills between noon-1pm. Storms
today will generally be high-based with most areas staying dry. A few
elevated dew points this morning, currently 54 degrees at DIA, will
keep at least a LOW chance for brief moderate to heavy rainfall,
especially if dew points are unable to mix out prior to storm
development this afternoon. The largest threat today will be a quick
0.50” in 10-20 minutes, rather than any long-lasting rainfall.
Skies will start to clear by sunset with hazy and dry conditions
continuing into the overnight. Temperatures this evening will drop
into the low 60s on the plains with upper 50s to around 60 degrees
along the foothills.
STORM RAINFALL POTENTIAL AND DURATION: Typical showers/thunderstorms
will produce a trace to 0.25” total in 10-30 minutes. A moderate to
strong thunderstorm will produce 0.25-0.50” total in 10-30 minutes.
WORST CASE SCENARIO: A strong stationary thunderstorm, or training of
thunderstorms will have the potential to produce up to 1.00” total
in 30-60 minutes.
A LOOK AHEAD: Hot and dry conditions are expected tomorrow with a very
slight chance for a few high-based showers/thunderstorms along the
foothills in the afternoon and early evening. Tomorrow high
temperatures will once again reach the upper 90s under mostly sunny
skies. A shift in the upper-level flow Sunday will usher in some
monsoonal moisture into the region bringing a better chance for
afternoon and evening showers/thunderstorms. Similar conditions remain
in place Monday with continued southwesterly flow aloft with an
increase in overall moisture which will bring another chance for
showers and thunderstorms.
LOCATION
PRIME TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
200 PM TO 800 PM
Trace (40%) to 0.25" (20%) to 0.5" (10%)
LOW
Arapahoe
200 PM TO 800 PM
Trace (40%) to 0.25" (20%) to 0.5" (10%)
LOW
Boulder
200 PM TO 800 PM
Trace (40%) to 0.25" (20%) to 0.5" (10%)
LOW
Broomfield
200 PM TO 800 PM
Trace (40%) to 0.25" (20%) to 0.5" (10%)
LOW
Denver
200 PM TO 800 PM
Trace (40%) to 0.25" (20%) to 0.5" (10%)
LOW
Douglas
200 PM TO 800 PM
Trace (40%) to 0.25" (20%) to 0.5" (10%)
LOW
Jefferson
200 PM TO 800 PM
Trace (40%) to 0.25" (20%) to 0.5" (10%)
LOW
Foothills above 6500ft
Boulder
100 PM TO 700 PM
Trace (50%) to 0.25" (25%) to 0.5" (10%)
LOW
Douglas
100 PM TO 700 PM
Trace (50%) to 0.25" (25%) to 0.5" (10%)
LOW
Jefferson
100 PM TO 700 PM
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]
4 months, 3 weeks
Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 942 AM Thu August 1, 2024
Forecaster: Laura Smith
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
Smoky Skies with slight chances for Isolated Storms.
Smoke from several wildfires along the Front Range foothills will
inundate the Urban Corridor today as light upper-level winds carry
smoke plumes onto the plains. Smoke aside, hot conditions will
continue as afternoon temperatures reach the upper 90s. A few
locations may reach or exceed 100°F today (which is about 10°F above
normal). Dewpoints will be around 40°F, with precipitable water
(PWAT) values around 0.65”. These conditions will support a slight
chance for isolated showers and thunderstorms this afternoon and
evening, primarily across the foothills and Palmer Divide.
STORM RAINFALL POTENTIAL AND DURATION: Showers and thunderstorms today
have the potential to produce up to 0.10” in 10-30 minutes.
WORST CASE SCENARIO: A slow-moving stronger thunderstorm may be
capable of producing 0.20” or more in 30 minutes or less.
A LOOK AHEAD: The long-range forecast remains somewhat underwhelming
with the arrival of an upper-level disturbance. Atmospheric moisture
will increase slightly, resulting in PWAT values up to 0.75” and dew
points in the mid 40s. No significant precipitation is expected with
this pattern, but there is a slight chance for isolated showers and
storms Friday and Saturday.
LOCATION
PRIME TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
200 PM TO 800 PM
Trace (15%) to 0.05" (10%) to 0.1" (5%)
NONE
Arapahoe
200 PM TO 800 PM
Trace (15%) to 0.05" (10%) to 0.1" (5%)
NONE
Boulder
200 PM TO 800 PM
Trace (15%) to 0.05" (10%) to 0.1" (5%)
NONE
Broomfield
200 PM TO 800 PM
Trace (15%) to 0.05" (10%) to 0.1" (5%)
NONE
Denver
200 PM TO 800 PM
Trace (15%) to 0.05" (10%) to 0.1" (5%)
NONE
Douglas
200 PM TO 800 PM
Trace (20%) to 0.05" (15%) to 0.1" (10%)
NONE
Jefferson
200 PM TO 800 PM
Trace (20%) to 0.05" (15%) to 0.1" (10%)
NONE
Foothills above 6500ft
Boulder
200 PM TO 800 PM
Trace (20%) to 0.05" (15%) to 0.1" (10%)
NONE
Douglas
200 PM TO 800 PM
Trace (20%) to 0.05" (15%) to 0.1" (10%)
NONE
Jefferson
200 PM TO 800 PM
Trace (20%) to 0.05" (15%) to 0.1" (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]
4 months, 3 weeks