289
FXUS65 KBOU 150621
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1221 AM MDT Thu Aug 15 2024

.KEY MESSAGES...

- A bit less thunderstorm activity today with lower flood/severe
  threats. Much less on Thursday.

- Hotter and drier Friday and into the weekend.

- Precipitation chances increase beginning Sunday, with some
  moderation in temperature.

&&

.UPDATE...
Issued at 734 PM MDT Wed Aug 14 2024

Going forecast on track with scattered to isolated showers and
thunderstorms slowly coming to an end by midnight. Main threat
with the remaining showers and storms will be gusty outflow winds,
especially with the activity crossing the Continental Divide.
Gusts to 50 mph will be possible with this. Airmass continue to
dry tonight and Thursday with isolated high-based convection
expected for Thursday.

&&

.SHORT TERM /Through Thursday/...
Issued at 300 PM MDT Wed Aug 14 2024

GOES-18 West continues to display dry air throughout northeastern
Colorado. With limited instability and shear, scattered showers and
storms shouldn`t pack a punch compared to the last few days this
week. Generally, METARs shown 35-40 mph gusts as showers and storms
push eastward. This should continue until early evening. With storms
moving quickly, the flood threat is much lower through this evening.
Tonight, temperatures are near normal across the CWA.

A ridge pattern builds into the region starting Thursday. As
moisture remains limited Thursday afternoon, high based isolated to
scattered showers are possible mainly for the mountains and
foothills. Weak MLCAPE values at 300 J/kg and SHIP values near 0.4
could lead to a few stronger storms producing small hail. DCAPE
values exceeding 1000 J/kg thus it possible storms could produce
wind gusts up to 40 mph. There is some uncertainty in storms
crossing the Divide into the I-25 corridor. With sufficient
heating and low level moisture, a few gusty showers are possible.
Expect similar temperatures once more.

&&

.LONG TERM /Thursday night through Wednesday/...
Issued at 300 PM MDT Wed Aug 14 2024

There will be a weak shortwave trough within the broader ridging that
moves across Colorado Thursday night into Friday morning. This
will provide just enough forcing for a few showers and weak storms
to form on the far eastern plains. PoPs were increased slightly to
indicate in the forecast that measurable rain could occur.

Later in the day on Friday, an upper level ridge will strengthen
over the Four Corners area with warm, westerly flow over our
forecast area. The strong subsident flow will keep conditions dry
and there will be mostly sunny skies. These factors will lead to
temperatures warming above normal with highs reaching the low to
mid 90s across the urban corridor and plains.

On Saturday, the ridge will move closer to our forecast area and
there will continue to be strong subsidence. There will again be
mostly sunny skies with only a stray shower or two. An additional
degree or two Celsius of warming at 700 mb will allow temperatures
to warm 3-5 F compared to Friday. Highs in the mid to upper 90s
are expected across lower elevations. Some of the ensemble
members have DIA reaching 100 F. Due to the recent moisture and
700 mb temperatures not being quite warm enough for triple digit
heat, it seems unlikely DIA or Denver would actually reach 100 F.
The forecast for Denver calls for a high of 97 F which would be 1
degree short of the daily record high of 98 F set in 2020. That
record high is well within reach.

On Sunday and into early next work week, the ridge aloft will
drift eastward towards the panhandle of Oklahoma. At the surface,
there will be southeasterly flow on the plains which will draw
healthy moisture farther west. The moisture will likely reach the
foothills and even though there is a strong cap aloft, the
additional instability and upslope flow in the higher terrain will
result in scattered storms developing in the afternoon and
evening each day. With light flow aloft and ample moisture, these
storms could pose a flash flooding risk over the recent burn
areas. Highs will moderate a bit through the middle of the week
but will still be slightly above normal.

&&

.AVIATION /06Z TAFS through 06Z Friday/...
Issued at 1215 AM MDT Thu Aug 15 2024

VFR through Thursday. Isolated high based showers are expected
near Denver 21z-03z. There is a 20% chance of a wind shift or two
with gusts to 30 knots.

&&

.HYDROLOGY...
Issued at 300 PM MDT Wed Aug 14 2024

Drier air will lead to limited thunderstorm coverage Thursday
through Saturday, with a low threat of flash flooding for burn
scars.

There will be at least a limited threat of flash flooding on the
burn areas Sunday through Wednesday as moisture returns to our
forecast area. Scattered storms are expected over the higher
terrain each day.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

UPDATE...Meier
SHORT TERM...AD
LONG TERM...Danielson
AVIATION...Gimmestad
HYDROLOGY...AD/Danielson