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Area forecast discussion 
National Weather Service Pueblo Colorado
659 PM MDT Wednesday Apr 1 2015

issued at 657 PM MDT Wednesday Apr 1 2015

Update for expiration of the red flag warning for portions of the
forecast area this evening. Red flag for portions of the area for
tomorrow afternoon remains in effect. Moore


Short term...(this evening through thursday)
issued at 346 PM MDT Wednesday Apr 1 2015 danger continues and returns to some areas tomorrow while
other areas turn colder and wetter...

Increasing westerly flow over the forecast area next 24 hours. This
flow will keep the fire danger high over parts of the area right on
through Thursday. So far today...have been hitting wind criteria
quite well in the usual locations across the San Luis valley and
adjacent to the mountains. These areas have seen frequent gusts
over 25 miles per hour today. The humidities have been kind of marginal...
right around 15 percent. Farther east across the klhx
and klaa...the winds have been hitting occasionally but not for 3
hours yet. But...still a few hours to go. So...all in all...the
red flag warning is verifying pretty well today.

As advertised...some high based convection is moving across the area
today...associated with a weak upper disturbance move through. Even
a snow shower at Leadville with a temperature of 37 degrees this
past hour. This trend will continue into the evening...with primary
threats of lightning and wind gusts to 45 miles per hour from any storms. There
could even been a few stragglers drifting across through the
night if the models are correct.

Behind the disturbance that is moving through this afternoon...a
cold front will make a run south through the plains overnight...and
bank up against the eastern slopes of the mountains. This front
will bring low level upslope flow to the region by Friday morning...
accompanied by low clouds over most of the well as some
scattered precipitation...mainly banked up against the mountains in
and around the Pikes Peak region...including El Paso and Teller
counties. Mostly rain showers...but could be some wet snow mixed in
by morning as temperatures are marginal for rain versus snow.
Elsewhere...just a spotty light shower here and there.

As the morning progresses...the front looks like it will make a
quick retreat from the plains plains adjacent to the mountains
south of Pueblo. This will allow a resurgence of red flag
conditions from the San Luis valley eastward across Las Animas
County from noon to 6 PM. Other areas south of Highway 50 will also
see the front retreat and westerly winds return...but looks like
humidities will remain high enough to stay out of red flag criteria.

More afternoon and evening showers expected to develop Thursday
afternoon...mainly along and north of the frontal boundary...which
should be somewhere in the vicinity of Highway 50. Models are
also showing some convective development over the far eastern plains
in the afternoon...where low level moisture looks better and winds
are more from the south to southeast...rather than southwest.

Snow levels could drop to around 7000 feet by Thursday morning over
the Pikes Peak region. Otherwise...snow levels will still be pretty
high through Thursday...generally above 10000 feet. Any snowfall
accumulations tonight through Thursday will generally be in the 1
to 3 inch range...above the respective snow levels.

Long term...(thursday night through wednesday)
issued at 346 PM MDT Wednesday Apr 1 2015

..rapidly changing conditions possible Thursday evening...

Thursday night-Friday...strong west to northwest flow aloft across
the region Thursday night slowly moderates through the day on Friday
as broad upper trough and associated jet core translate across the
state. Latest models continue to support best lift with this system
to remain north of the area across the northern Front Range and
northeast plains. However...passing jet core across the area
Thursday night allows for a strong cold front to push south across
the Palmer Divide late Thursday afternoon...which continues across
all of southeast plains through the late evening and overnight
hours. Passing front to be marked with gusty northerly winds of 20
to 40 miles per hour along developing rain and mixed rain and snow showers with
strong frontogenetic forcing. Surface-700 mb flow prognosticated to remain
northerly through the evening...with best chances of accumulating
snowfall still expected across portions of the Pikes Peak region and
areas along the Palmer Divide. Grids currently indicating snowfall
of 2-6 inches across Pikes Peak and Teller County with 1-3 inches
across northern El Paso County and a trace up to 2 inches across the
rest of the southeast mts and plains. Will continue to monitor later
model runs...though may need an impact based advisory for portions
of the Pikes Peak area Thursday night with rapidly deteriorating
conditions possible for the Thursday evening commute.

System passes overnight with clearing skies expected late Friday
morning through the early afternoon. However...with cold air mass
slowly retreating...temperatures to be below seasonal averages with highs
in 40s to middle 50s across the lower elevations and 30s to lower
40s across the higher terrain.

Saturday-Monday...moderate west to southwest flow aloft with minor
embedded disturbances prognosticated across the region through Easter
weekend...which looks to keep generally dry...warm and breezy
conditions in place across the area. Temperatures look to warm back
to at and slightly above seasonal averages with possible critical
fire conditions in the afternoon and early evenings with mixing of
stronger winds aloft. Could see a few showers across the Continental Divide
Monday afternoon as moisture increases across the area ahead of a
weather system moving into the Great Basin region.

Tuesday-Wednesday...a cooler and a more unsettled weather pattern
still looks to be in the offing as a broad upper trough across the
Great Basin moves across The Rockies. cold and how wet
still remains to be seen...with the latest models having run to run
differences with how far south the system moves. The 12z European model (ecmwf) is now
moving the system across the northern rockies...where as the its
previous 00z run had the system digging across The Four Corners with
the 12z GFS run a little further south with the system than its
ensemble mean. At any rate...increasing slight and chance probability of precipitation from
west to east and temperates cooling through the period to suffice
for now.


Aviation...(for the 00z tafs through 00z Thursday evening)
issued at 346 PM MDT Wednesday Apr 1 2015

VFR conditions will continue for the kcos and kpub taf sites through
about 06z-07z Thursday. A few late afternoon and early evening high
based storms will track across the area...and this will lead to some
erratic and gusty winds. Some localized gusts in the 40 to 45 miles per hour
range will be addition to more widespread winds from
the west to southwest in the 20-30 miles per hour range. A cold front will drop
southward across the plains after 03z...leading to a wind shift
coming from the north to northeast tonight. The front will lead to a
period of MVFR to IFR ceilings Thursday morning...along and east of the the 10z-18z period...along with the potential for
isolated to scattered rain or snow showers. Gusty westerly winds
will return to the San Luis valley and the plains south of Highway
50 Thursday the cold front retreats to the north and
east through the day. Kals will likely remain VFR through the


Pub watches/warnings/advisories...
red flag warning from noon to 6 PM MDT Thursday for coz224-230-



short term...lw

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