National Weather Service Forecast Discussion

Thornton Weather Forecast   
Today's Forecast Story   
346
FXUS65 KBOU 250527
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1127 PM MDT Mon Mar 24 2025

.KEY MESSAGES...

- Mostly dry weather Tuesday into Friday, with above normal
  temperatures all four days.

- Cooler with a chance of precipitation Friday night into Sunday.

&&

.UPDATE...
Issued at 757 PM MDT Mon Mar 24 2025

Still have some mid and high level moisture moving across in NW
flow aloft. Still could see a slight chc of -shsn in the nrn mtns
overnight. Across the plains, can`t rule out some virga over the
far nern plains where there is an upper level jet in place.
However, the chc of measurable precip is very low.

&&

.SHORT TERM /Through Tuesday/...
Issued at 241 PM MDT Mon Mar 24 2025

Gusty winds have been persistent across most of our forecast area
today. Gusts have been around 35-40 mph across the Denver metro
and northeast plains. Thankfully, high clouds have kept
temperatures down a couple of degrees below forecast which is
keeping relative humidity above 20% across the plains. Elevated
fire weather conditions will continue through the afternoon.

There will be some slight cold air advection at 700 mb tonight as
the mid to upper level jet moves away from our area. A high
pressure system will develop over eastern Colorado tomorrow which
will result in much lighter winds. High temperatures will be about
the same as today as there will be more sunshine but slightly
cooler temperatures at 700mb. The lighter winds will also mean
fire weather concerns will be lower tomorrow. Otherwise, it will
be dry and a good day for getting outside.

&&

.LONG TERM /Tuesday night through Monday/...
Issued at 241 PM MDT Mon Mar 24 2025

Models show upper ridging to dominate the CWA`s weather Tuesday
night through Thursday night. The flow aloft is very weak all five
periods. The QG Omega fields show benign synoptic scale vertical
velocity for the CWA into Thursday, with weak downward motion
Thursday night. The low level pressure and winds fields show
normal diurnal wind patterns with fairly weak speeds for the next
few days.

For moisture, cross sections show limited cloudiness for the CWA
well into Friday. There may be a bit of high cloudiness once and
while. There could also be enough moisture for a few afternoon
convective showers in the mountains only.  Nothing significant.

For temperatures, Wednesday`s highs are about 15 degrees above
seasonal normals over the plains, with mid 70s expected.  It looks a
bit warmer on Thursday with highs close to 80 over the plains.

For the later days, Friday through Monday, southwesterly flow aloft
is progged all of Friday and Friday night into Saturday now, with
the weak upper trough moving through later in the day on into
Sunday morning. That certainly slowed down from yesterday`s 12Z
model runs. Also, the precipitation production does not look
robust with the trough at all. However, a few ensemble members do
show decent amounts of QPF. Spring so far has been pretty dry for
the CWA. For temperatures, Friday`s highs continue well above
seasonal normals, with Saturday and Suanday`s readings right
around normals. Monday warms up again.

&&

.AVIATION /06Z TAFS through 06Z Wednesday/...
Issued at 1126 PM MDT Mon Mar 24 2025

Light northwest winds still persist to start this period, but
they`ll likely turn more southwesterly 09Z-11Z, and then light
and variable 14Z-17Z. There is a couple hour period in that last
transition (11Z-15Z) that a more south/southeast wind could
prevail, but speeds would be light and less than 8 kts. A
north/northeast wind is then expected to develop 17Z-19Z with
daytime heating and mixing, before eventually returning to
east-southeast-south through the 01Z-05Z period tonight.

VFR will persist, although a SCT-BKN deck around 8,000 ft AGL is
expected to develop for a few hours 00Z-07Z Wednesday. Cloud decks
should be just above any concern for IMC.

&&

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

&&

$$

UPDATE...RPK
SHORT TERM...Danielson
LONG TERM....rjk
AVIATION...Barjenbruch

NWS BOU Office Area Forecast Discussion