Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 908 AM Fri September 20, 2024
Forecaster: Justin Brooks
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
Warm, mostly sunny, with another dry day today.
Today will once again be mild and dry throughout the day and
evening. A low-pressure system is slowly moving across the desert
southwest today, leading to southwesterly flow aloft across the
region. This southwesterly flow will bring mild and dry conditions for
the District today and this evening. Temperatures are expected to
reach the mid to upper 80s this afternoon, mostly sunny skies.
Overnight temperatures will drop into the low to mid 50s on the plains
with upper 40s to around 50 degrees along the foothills.
STORM RAINFALL POTENTIAL AND DURATION: No precipitation is expected
today or this evening.
A LOOK AHEAD: Cooler tomorrow as the disturbance moves into the region
bringing a good chance of off and on showers during the day, lasting
into the evening hours, overnight and into Sunday. Storm strength will
hinge on how much daytime heating occurs with high temperatures only
expected to reach the upper 60s to around 70 degrees. These cooler
temperatures could potentially result in just shower activity with
very little convection during the day decreasing chances for any heavy
rainfall, with a better chance for more persistent rainfall rather
than thunderstorm activity. Some showers could be moderate to briefly
heavy at times with upwards of and inch of total precipitation during
this event. Off and on showers may persist through the day Sunday,
finally tapering off into the afternoon/evening. Sunday will be even
cooler with high temperatures remaining in the mid to upper 50s.
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
3 months
Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 859 AM Thu September 19, 2024
Forecaster: Justin Brooks
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
Another warm, sunny, and dry today.
Westerly flow aloft will continue to usher in mild and dry
conditions across the District today and this evening. Temperatures
are expected to reach the low to mid 80s this afternoon under mostly
sunny skies. Overnight temperatures will drop into the mid 50s on the
plains with upper 40s to low 50s along the foothills.
STORM RAINFALL POTENTIAL AND DURATION: No precipitation is expected
today or this evening.
A LOOK AHEAD: Slightly warmer tomorrow as high temperatures reach the
mid to upper 80s. Mild and dry conditions are likely to continue
throughout the day and evening. Cooler Saturday with a good chance of
off and on showers during the day, lasting into the evening hours.
Storm strength will hinge on how much daytime heating occurs with high
temperatures only expected to reach the upper 60s to around 70
degrees. These cooler temperatures could potentially result in just
shower activity with very little convection during the day decreasing
chances for any moderate to heavy rainfall, with a better chance for
more persistent rainfall rather than thunderstorm activity.
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
3 months
Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 859 AM Wed September 18, 2024
Forecaster: Justin Brooks
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
Warm, sunny, and dry today.
West to southwesterly flow aloft will usher in mild and dry
conditions across the District today. Temperatures will reach the low
to mid 80s this afternoon under sunny skies. Mild and dry conditions
are expected to continue into the evening with clear skies. Overnight
temperatures will drop into the upper 40s to around 50 degrees on the
plains with mid to upper 40s along the foothills.
STORM RAINFALL POTENTIAL AND DURATION: No precipitation is expected
today or this evening.
A LOOK AHEAD: Similar conditions remain in place tomorrow with
continued sunny, mild and dry conditions throughout the day. High
temperatures will once again reach the low to mid 80s during the
afternoon with low 50s overnight and into Friday. Warmer Friday as
highs reach the mid to upper 80s. A very slight chance for a few
showers and possibly a thunderstorm or two during the late
afternoon/evening with minimal impacts expected at this time. Cooler
Saturday with a good chance of off and on showers during the day,
lasting into the evening hours. Storm strength will hinge on how much
daytime heating occurs with high temperatures only expected to reach
the upper 60s to low 70s. These cooler temperatures could potentially
result in just shower activity with very little convection during the
day decreasing chances for any moderate to heavy rainfall.
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
3 months
Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 849 AM Tue September 17, 2024
Forecaster: Aaron O
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
Strong Cold Front this Afternoon with Thunderstorms Likley
Another day with highs in the mid to upper 80s as a cold front is
expected to move through The District this afternoon. Dew points are
expected to be in the mid 30s to the low 40s, and with Precipitable
water values between 0.60” to 0.70”, will bring a LOW chance of
Message level rainfall as scattered to widespread thunderstorms are
expected this afternoon.
Storms today will be quite fast as the SSW to NNE storm motion of
25-35 mph will significantly limit point rainfall amount. However,
outflow boundaries from a stronger storm will have the potential for
some erratic storm motions. These erratic storms will have the best
potential for moderate to heavy rainfall with the biggest threat being
a quick 0.5” in 10-20 minutes rather than any long-lasting rainfall.
One round of storms is likely today with the best chance between
2-6pm. A few storms could become severe today, mainly for gusty wind
60+ mph and possibly hail up to 1.0”, favoring areas east of I-25.
Chances for thunderstorms will end before sunset as the cold front
moves out of The District and into the Eastern Plains, with skies
clearing through the evening. Overnight conditions are expected to be
mild and dry as temperatures drop to around 50 degrees on the plains
with mid to upper 40s along the foothills.
STORM RAINFALL POTENTIAL AND DURATION: Typical showers and
thunderstorms will produce rainfall rates of up to 0.25” total in
15-30 minutes. Moderate to strong thunderstorms will produce between
0.25"-0.50" total in 10-30 minutes.
WORST CASE SCENARIO: A strong stationary thunderstorm or training of
thunderstorms have the potential to produce up to 1.00” total
rainfall 30-60 minutes.
A LOOK AHEAD: For the next several days, a high pressure system will
build over the Intermountain West, keeping The District dry for the
rest of the week. Next chance for precipitation will be this weekend
with a passing weak cold front bringing our first real winter-like
storm set up, with shallow and light precipitation for the afternoon
and evening on Saturday.
LOCATION
PRIME TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
200 PM TO 600 PM
Trace (50%) to 0.3" (25%) to 0.5" (10%)
LOW
Arapahoe
200 PM TO 600 PM
Trace (50%) to 0.3" (25%) to 0.5" (10%)
LOW
Boulder
200 PM TO 600 PM
Trace (50%) to 0.3" (25%) to 0.5" (10%)
LOW
Broomfield
200 PM TO 600 PM
Trace (50%) to 0.3" (25%) to 0.5" (10%)
LOW
Denver
200 PM TO 600 PM
Trace (50%) to 0.3" (25%) to 0.5" (10%)
LOW
Douglas
200 PM TO 600 PM
Trace (50%) to 0.3" (25%) to 0.5" (10%)
LOW
Jefferson
200 PM TO 600 PM
Trace (50%) to 0.3" (25%) to 0.5" (10%)
LOW
Foothills above 6500ft
Boulder
200 PM TO 600 PM
Trace (60%) to 0.3" (30%) to 0.5" (15%)
LOW
Douglas
200 PM TO 600 PM
Trace (60%) to 0.3" (30%) to 0.5" (15%)
LOW
Jefferson
200 PM TO 600 PM
Trace (60%) to 0.3" (30%) 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]
3 months, 1 week
Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 850 AM Mon September 16, 2024
Forecaster: Aaron O
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
More Very Isolated Showers this Afternoon with Mostly Sunny Skies
Slightly warmer temperatures today, with highs in the low to mid
80s. Dew points will drop this afternoon to the low to mid 30s,
limiting any significant point rainfall amounts. Precipitable water
values are higher than yesterday, with 0.65” to 0.80”, but due to
the low dew points and drying winds from the mountains point rainfall
amounts will be significantly limited. Storm motion today will be SW
to NE at 20-25 mph, which will also limit rainfall amounts. Rainfall
amounts today should remain well below Message level amounts for The
District. Storms should weaken around sunset and fully dissipate an
hour or two after sunset, with skies clearing overnight.
STORM RAINFALL POTENTIAL AND DURATION: Typical showers will produce
rainfall rates of up to 0.10” total in 15-30 minutes.
WORST CASE SCENARIO: A moderate to strong thunderstorm has the
potential to produce up to 0.30” total rainfall 15-30 minutes.
A LOOK AHEAD: Tomorrow will have a strong cold front move through The
District in the afternoon. PWAT values of 0.70” to 0.80” and dew
points in the low to mid 40s could have the potential to create
Message level rainfall. Storm speeds should be quite high, 15-30 mph,
which will limit point rainfall amounts, but storms still could
possibly meet Message level criteria. A storm or two could possibly
reach severe criteria of 60 mph gusts and hail up to 1 inch in
diameter. The cold front should reach The District by the early
afternoon. After the cold front leaves The District should dry out and
continue to stay dry for the rest of the work week.
LOCATION
PRIME TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
100 PM TO 900 PM
Trace (30%) to 0.1" (20%) to 0.2" (10%)
NONE
Arapahoe
100 PM TO 900 PM
Trace (30%) to 0.1" (20%) to 0.2" (10%)
NONE
Boulder
100 PM TO 900 PM
Trace (30%) to 0.1" (20%) to 0.2" (10%)
NONE
Broomfield
100 PM TO 900 PM
Trace (30%) to 0.1" (20%) to 0.2" (10%)
NONE
Denver
100 PM TO 900 PM
Trace (30%) to 0.1" (20%) to 0.2" (10%)
NONE
Douglas
100 PM TO 900 PM
Trace (30%) to 0.1" (20%) to 0.2" (10%)
NONE
Jefferson
100 PM TO 900 PM
Trace (30%) to 0.1" (20%) to 0.2" (10%)
NONE
Foothills above 6500ft
Boulder
100 PM TO 900 PM
Trace (40%) to 0.1" (30%) to 0.2" (20%)
NONE
Douglas
100 PM TO 900 PM
Trace (40%) to 0.1" (30%) to 0.2" (20%)
NONE
Jefferson
100 PM TO 900 PM
Trace (40%) to 0.1" (30%) to 0.2" (20%)
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]
3 months, 1 week
Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 934 AM Sun September 15, 2024
Forecaster: Aaron O
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
Isolated Showers this Afternoon with Mostly Sunny Skies
Today will be on the warmer side, with afternoon temperatures in the
upper 80s. Dewpoints are in the upper 30s to upper 40s across The
District and are expected to decrease throughout the day. Due to
downsloping winds, the afternoon dewpoints will likley mix out into
the low 30s, possibly as low as the upper 20s, which should limit
rainfall amounts from an approaching shortwave this afternoon/evening.
Precipitable water values are expected to be between 0.50” and
0.65”, which could potentially bring some moderate rainfall amounts,
but due to lower surface dewpoints and 15-20 mph SSW to NNE storm
motions, rainfall should remain below Message level amounts. Any
convection will weaken after sunset and any shower activity will
dissipate by 9 pm, with skies mostly clearing out overnight.
STORM RAINFALL POTENTIAL AND DURATION: Typical showers will produce
rainfall rates of up to 0.10” total in 15-30 minutes.
WORST CASE SCENARIO: A moderate to strong thunderstorm has the
potential to produce up to 0.30” total rainfall 15-30 minutes.
A LOOK AHEAD: Tomorrow will be slightly cooler and have a much lesser
chance of convection due to a strong zonal flow creating downsloping
across The District. Most convection will remain well west of The
District, around the Continental Divide and possibly the higher
elevations. An isolated shower or two could make it off the
Continental Divide and into The District but will be very limited in
point rainfall amounts as dewpoints and PWAT values will remain low.
Tuesday will have a cold frontal passage, inducing one wave of
convection. This wave will be heavily impacted by downsloping,
limiting point rainfall amounts to be minimal. Wednesday through
Friday will remain dry due to a high pressure system across Colorado.
This weekend may see the first real winter-like upslope event post
cold frontal passage.
LOCATION
PRIME TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
100 PM TO 800 PM
Trace (30%) to 0.1" (15%) to 0.3" (5%)
NONE
Arapahoe
100 PM TO 800 PM
Trace (30%) to 0.1" (15%) to 0.3" (5%)
NONE
Boulder
100 PM TO 800 PM
Trace (30%) to 0.1" (15%) to 0.3" (5%)
NONE
Broomfield
100 PM TO 800 PM
Trace (30%) to 0.1" (15%) to 0.3" (5%)
NONE
Denver
100 PM TO 800 PM
Trace (30%) to 0.1" (15%) to 0.3" (5%)
NONE
Douglas
100 PM TO 800 PM
Trace (30%) to 0.1" (15%) to 0.3" (5%)
NONE
Jefferson
100 PM TO 800 PM
Trace (30%) to 0.1" (15%) to 0.3" (5%)
NONE
Foothills above 6500ft
Boulder
100 PM TO 800 PM
Trace (30%) to 0.1" (15%) to 0.3" (5%)
NONE
Douglas
100 PM TO 800 PM
Trace (30%) to 0.1" (15%) to 0.3" (5%)
NONE
Jefferson
100 PM TO 800 PM
Trace (30%) to 0.1" (15%) 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]
3 months, 1 week
Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 903 AM Sat September 14, 2024
Forecaster: Aaron O'Brien
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
Dry, Warm, and Calmer Conditions for The District Today
Similar conditions as yesterday with weak zonal flow in the upper
atmosphere, which will continue to inhibit any sort of convection
today with weak downsloping drying out what little moisture is left.
Precipitable water values continue to lower with 0.35”-0.40”, with
no rainfall expected. Winds today will likely remain below 10 mph with
no gusty conditions and yesterday’s haze has moved out of the State
of Colorado. Overall conditions will be warm, dry, and overall
pleasant.
STORM RAINFALL POTENTIAL AND DURATION: No rainfall is expected within
the District today.
A LOOK AHEAD: Moisture conditions and afternoon temperatures will
remain relatively the same for tomorrow with PWAT values remaining
around 0.40”, which will likely limit most convection. A possible
weak short wave could move through The District, depending on how
south and east the Jet Stream will dig into the Desert Southwest. This
will create a SSW to NNE storm motion, which can inhibit some moisture
due to downsloping off the Palmer Divide and partly the Front Range,
but convection will entirely depend on the positioning of the Jet
Stream. If this short wave does reach The District, any convection
will likely not produce much due to the low moisture content and
downsloping. Monday’s chances for precipitation increases as this
low pressure system associated with the digging Jet Stream introduces
more moisture into The District, but by Tuesday and Wednesday, zonal
flow returns and decreases the precipitation chances significantly.
This zonal pattern is likely to continue through the rest of the week
and into the beginning of the weekend.
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
3 months, 1 week
Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 910 AM Fri September 13, 2024
Forecaster: Tim Tonge
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
Cooler, continued dry and breezy conditions
A relatively stagnant upper-level flow pattern will continue the
filtering of dry air from the southwest into Colorado and the District
today. This has dropped precipitable water values District-wide to
around 0.40", and no rainfall is expected in the District today. Gusty
winds will linger through the day, though not as strong or widespread
as they were yesterday, favoring mainly the Palmer Divide and eastern
portions of the District. There's a slight haze in the air this
morning from wildfires in southern California, but the amount of smoke
is less than previously anticipated, and overall conditions should
make for a lovely mid September day after a cold front passed last
night and dropped temperatures by about 10 degrees from yesterday.
STORM RAINFALL POTENTIAL AND DURATION: No rainfall is expected within
the District today.
A LOOK AHEAD: Warming back up towards the upper 80s over the next few
days, with a very isolated chance of some showers over the high
country Sunday and otherwise dry conditions. Indications of a change
in the pattern are present late Monday/Tuesday as a potent trough
marches across the Great Basin towards Colorado. This will arrive with
rainfall chances Tuesday, and our first truly fall-like temperatures
appear likely by Thursday of next week.
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
3 months, 1 week
Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 1239 PM Thu September 12, 2024
Forecaster: Tim Tonge
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
Potential final 90 degree day of 2024, dry and windy
The dry slot of a potent storm system over Wyoming and Montana is
placed firmly over Colorado today. Upper-level flow is out of the
southwest, and hot, dry, desert air has cleared out available moisture
from the District, and no storms are expected today as a result.
Temperatures across the District are likely to hover at or just below
90 this afternoon. As the aforementioned storm system pushes east, a
surface low will deepen over southeastern Wyoming, which in turn will
cause winds to pick up across much of Colorado today. Much of the
District will see consistent winds of 15-20mph through the afternoon
and evening with gusts to 40mph possible, especially over the Palmer
Divide and in eastern portions of the District. Winds will calm after
sunset.
Large wildfires east of Los Angeles have produced a plume of smoke
that is currently draped across the majority of the desert southwest.
Under southwesterly flow, this smoke will arrive in Colorado around
sunset and produce hazy conditions and poor air quality overnight.
STORM RAINFALL POTENTIAL AND DURATION: No rainfall is expected in the
District today.
A LOOK AHEAD: The thunderstorm season has essentially come to an end,
with the only upcoming chances for rainfall near the District coming
Sunday, and even Sunday the storms appear highly isolated and
contained to the high country outside the District. Otherwise, a
pleasant stretch of fall days is ahead until a shift in the weather
pattern brings back a chance of rainfall and cooler temps mid/late
next week.
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.
MHFD Flood Prediction Center: 303-458-0789 F2P2 Website
[http://udfcd.org/Flash+Flood+Prediction+Program]
3 months, 1 week
Flash Flood Prediction Program
by f2p2＠udfcd.org
Time: 855 AM Wed September 11, 2024
Forecaster: Justin Brooks
-------------------------
Heavy Precipitation Outlook
Flash Flood Prediction Program
-------------------------
Warm, slight uptick in moisture supporting scattered gusty showers
Upper-level moisture out ahead of a potent storm system over the
Pacific Northwest will be overhead today, coupled with a slight uptick
in surface moisture as well. This will support one of the final days
with message issuance potential for the summer thunderstorm season.
Storm coverage will be isolated/scattered once daytime heating pushes
temperatures in the high country past convective thresholds in the
early afternoon. Mostly small, weak, and gusty showers/t-storms will
meander east into the foothills and urban corridor in and around the
District shortly thereafter. Outflows from dying storms will have the
potential to spark other cells throughout the afternoon before storms
clear out fully before sunset.
Today comes with a small caveat: there is indications that a dryline
is likely to form on the plains east of the District. Drylines are
moisture boundaries that are ripe for strong thunderstorm development,
and should it develop closer to the metro than currently anticipated,
storms that form along it will have the highest chance of producing
message issuance-worthy rainfall. Chances of this occurrence within
the District are extremely low, but not zero, and favor the far
eastern portions of the District.
STORM RAINFALL POTENTIAL AND DURATION: Typical showers will produce a
trace-0.20" of rainfall in 10-30 minutes. Stronger thunderstorms will
produce 0.20-0.50" in 10-30 minutes.
WORST CASE SCENARIO: A strong/stationary thunderstorm, or training of
thunderstorms along the dryline, may be capable of producing 1.00" in
60 minutes or less.
A LOOK AHEAD: As summer starts to turn to fall, the Denver weather
pattern will begin to calm as it does each year. Tomorrow has a chance
to be DIA's final 90°F day of the year if it gets there under warm,
dry southwesterly flow. Calm, dry conditions will then arrive for the
weekend, with an extremely outside chance of a stray shower Sunday.
LOCATION
PRIME TIME
30-Minute Rainfall
and % Probability Message
Potential
Plains
Adams
200 PM TO 700 PM
Trace (30%) to 0.2" (20%) to 0.5" (10%)
LOW
Arapahoe
200 PM TO 700 PM
Trace (30%) to 0.2" (20%) to 0.5" (10%)
LOW
Boulder
200 PM TO 700 PM
Trace (30%) to 0.2" (20%) to 0.5" (10%)
LOW
Broomfield
200 PM TO 700 PM
Trace (30%) to 0.2" (20%) to 0.5" (10%)
LOW
Denver
200 PM TO 700 PM
Trace (30%) to 0.2" (20%) to 0.5" (10%)
LOW
Douglas
200 PM TO 700 PM
Trace (30%) to 0.2" (20%) to 0.5" (10%)
LOW
Jefferson
200 PM TO 700 PM
Trace (30%) to 0.2" (20%) to 0.5" (10%)
LOW
Foothills above 6500ft
Boulder
100 PM TO 700 PM
Trace (30%) to 0.2" (20%) to 0.5" (10%)
LOW
Douglas
100 PM TO 700 PM
Trace (30%) to 0.2" (20%) to 0.5" (10%)
LOW
Jefferson
100 PM TO 700 PM
Trace (30%) to 0.2" (20%) 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]
3 months, 1 week