Area Forecast Discussion
Issued by NWS Pueblo, CO

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37
FXUS65 KPUB 212155 CCA

Area Forecast Discussion...CORRECTED
National Weather Service Pueblo CO
355 PM MDT Wed Mar 21 2018

.SHORT TERM...(This evening through Thursday)
Issued at 339 PM MDT Wed Mar 21 2018

Upper ridge over the wrn U.S. today will continue to build overnight
and into Thursday, leading to warm and generally dry conditions
across srn CO. Have see some very sporadic flurries over the higher
peaks of the Continental Divide today, and with low/mid levels
moistening overnight and especially during the day Thu, suspect
we`ll continue to see some on/off very light snow through the
period, though no accumulations are expected. Elsewhere, mainly just
some occasional bouts of mid/upper level cloudiness overnight and
during the day Thu, with perhaps a gradual increase in surface winds
Thu afternoon as lee trough deepens and sw winds aloft begin to
accelerate. Clouds have helped trim a couple degf off max temps
today and will likely do so again on Thu, though with 700 mb temps
soaring into the 4-8C range, most of the plains will still push deep
into the 70s, and perhaps near 80f at usual warm spots near Lamar.
Mountains and interior valleys should see a mix of 50s/60s, with 40s
confined to just the highest elevations.

.LONG TERM...(Thursday night through Wednesday)
Issued at 339 PM MDT Wed Mar 21 2018

...Snow across the ContDvd Thursday night and Friday...
...Strong West Winds and High Fire Danger across the Plains Friday...

Thursday night-Friday night...Moderate to strong west to southwest
flow aloft remains progged across the region, as Eastern Pacific
energy ejects across the Great Basin Thursday night and continues
across the Central Rockies Friday and into the Central High Plains
Friday night. Moisture embedded within the increasing orographic
westerly flow aloft, along uvv ahead of the system will lead to
increasing coverage of snow showers across the ContDvd Thursday
night, along with a few possible thunder snow showers late Friday
morning and early afternoon, before showers diminish from south
to north later Friday afternoon and early evening. Current grids
indicating advisory type accumulations of 4 to 9 inches Thursday
night and Friday, with the highest amounts in the favored locales
of the Eastern San Juan and Eastern Sawatch Ranges.

Further east, models indicating the potential for strong and gusty
downslope winds across the southern Sangre de Cristo mountains late
Thursday night and into early Friday morning, though strongest winds
look to be for only a short duration, as winds aloft continue
increase. For now, I have increased wind gusts into the 60-70 mph
range across the higher elevations and will let later shifts get a
look at a few more model runs before deciding to issue any high wind
highlights. Strong winds aloft will mix down across the lower
elevations late Friday morning with gusty west winds of 25 to 45 mph
expected across the Southeast Plains through the afternoon. This,
combined with well above average temperatures in the upper 60s to
lower 80s and expected minimum humidity levels around 10 percent,
will lead to a dangerous fire weather conditions, with rapid spread
and growth possible, should a fire start. Current fire weather watch
for late Friday morning through early Friday evening looks good and
will remain in tact. Passing wave sends a weak and dry front across
Eastern Colorado Friday evening, with breezy northwesterly winds
Friday evening diminishing and becoming light upslope into early
Saturday morning.

Saturday-Sunday...Short wave ridging across the region Saturday
gives way to increasing southwesterly flow aloft through the day
Sunday, as more Eastern Pacific energy digs across the West Coast.
Dry weather is expected Saturday, with breezy southerly return flow
across the Southeast Plains leading to the potential for marginal
critical fire weather conditions Saturday afternoon. However, latest
models are indicating enough moisture in place to keep rh`s in the
15 to 20 percent and will not issue a fire weather weather attm. Dry
weather is expected across most the area on Sunday as well, save for
a few possible snow showers across the ContDvd later Sunday
afternoon. Breezy to windy conditions on Sunday could again lead
to critical fire weather conditions across portions of South
Central and Southeast Colorado. Temperatures on Saturday cool
slightly, though are still expected to be slightly above seasonal
levels in the 60s to lower 70s across the lower elevations, with
slightly warmer conditions expected on Sunday.

Sunday night-Wednesday...Latest models continue to indicate a cooler
and wetter pattern in the offing into early next week, though there
remains a lower confidence in timing and location of precipitation,
as models develop split flow pattern with a progressive northern
stream and a cutoff low in the southern stream across the Great
Basin. With noted model poor handling of cutoff systems, I stayed
close to a blended model solution, which keeps best chances of
precipitation over and near the higher terrain through the period.
The best chances for rain and snow showers across the Eastern
Plains, especially along and west of the I-25 Corridor, looks to be
later Monday and Tuesday, as low level upslope behind a passing cold
front in the northern stream, combines with moist southerly flow
aloft associated with an ejecting short wave from the main southern
stream cutoff low. At any rate, there will be a chance of much
needed precipitation areawide, along with at and below seasonal
temperatures into the middle of next week.


.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 339 PM MDT Wed Mar 21 2018

VFR conditions at all taf sites overnight and through the day Thu.
Briefly gusty winds this afternoon will diminish quickly overnight,
then pick up again Thu afternoon, with south winds gusting to 20 kts
at all terminals by 20z. Over the mountains, occasional -shsn will
continue overnight and through the day Thu along the Continental
Divide, and a few higher peaks may become briefly obscured.


Fire Weather Watch from Friday morning through Friday evening
for COZ226>237.



AVIATION...PETERSEN is the U.S. government's official web portal to all federal, state and local government web resources and services.