Special Weather Statement, NWS Pueblo, CO

Area Forecast Discussion
National Weather Service Pueblo CO
1144 AM MDT Sat Aug 4 2018

.SHORT TERM...(Today and tonight)
Issued at 434 AM MDT Sat Aug 4 2018

...Warmer and Drier Today...

Upper high pressure will build north and strengthen over Colorado
today.  This will result in broad scale descent over the region,
resulting in warmer and drier weather.  Satellite derived Total
Precipitable Water (TPW) estimates already indicate that drier air
is spreading into Colorado this morning.  After above normal values
yesterday, TPWs have already dropped below normal again over all but
the plains east of the I-25 corridor.  As drier air continues to
spread into Colorado from the west, eventually TPWs will be back
below normal again across all of southern Colorado. Regardless,
models still depict some weak upper level energy kicking off a few
showers or storms over the mountains and adjacent plains in the
afternoon. However, looking at the airmass below these storms, they
likely won't amount to much. Surface dewpoints below the storms are
generally forecast to be in the 30s or lower.  So, any storms that
develop will tend to be pretty high based, resulting primarily in
threats of lightning and gusty winds.  The threat of heavy rain or
hail should be pretty low today.  That's the good news.  The bad
news is that it will be hot.  Afternoon highs will be about 3 to 8
degrees above yesterday's readings and also above averages for this
time of year.  Intense summer heat is back!

.LONG TERM...(Sunday through Friday)
Issued at 434 AM MDT Sat Aug 4 2018

Models are remaining fairly consistent on the expected weather
scenario through the week, with a very hot day on Sunday giving way
to abundant showers and storms for Monday and Tuesday.

Sunday...A flat upper ridge of high pressure located over the
southern US will keep brisk west to southwest flow aloft across the
Four Corners region. A moisture feed out of Mexico will help fuel
isolated to low-end scattered showers and thunderstorms across the
forecast area beginning late morning, as temps climb rapidly into
the 90s to around 100F for the plains, and mid to upper 80s for the
high valleys. An upper disturbance will track across Montana and the
Dakotas Sunday aftn and eve, pushing a cold front down into Colorado
early Mon morning.

Monday and Tuesday...The upper ridge begins to amplify with the
ridge axis located west of the state. This will place the state
under northwest flow aloft. At the same time, the early morning cold
front will usher in easterly upslope flow at the sfc that will push
llvl moisture across the plains and up against the eastern mts. This
increasing moisture will fuel widespread thunderstorms Mon aftn and
eve, and the potential for flash flooding across area burn scars
will be a concern. Similar set-up for Tue, though coverage and
intensity will likely be more subdued. Temps both days are forecast
to be a bit cooler as increased cloud cover and pcpn will help cool
the mercury slightly. Look for highs on Mon in the 80s for the high
valleys and 80s to around 90F for the plains, then 80s for all areas
on Tue.

Wednesday through Friday...The upper ridge continues to strengthen
to the west through the rest of the work week, keeping Colorado
under northerly flow aloft. Pcpn chances will become more diurnal in
nature and tied more to the higher terrain, especially for Thu and
Fri. Temps will be very similar all three days, climbing into the
80s for most areas. Moore

&&

.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1134 AM MDT Sat Aug 4 2018

VFR conditions are expected at KCOS and KPUB over the next 24
hours, while KALS may see low clouds and fog develop early Sunday
morning, which would reduce CIGs and VIS. Thunderstorm coverage
will only be very isolated today over the mountains and adjacent
plains. KALS may see storms impact the terminal during the late
afternoon, while KCOS will more likely just see vicinity storms by
late afternoon and early evening. It is more likely that KPUB
will not have any thunderstorms, but there is still a very low
chance. Winds at all three sites will generally increase out of
the south/southeast during the day at 10-15 knots, before
weakening and becoming northerly again this evening.
Thunderstorm-generated outflow boundaries could cause brief gusty
winds and direction changes this afternoon/early evening at any of
the three TAF sites.

&&

.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SHORT TERM...LW
LONG TERM...MOORE
AVIATION...LINE

Hazardous Weather Outlook
National Weather Service Pueblo CO
1149 AM MDT Sat Aug 4 2018

COZ058>089-093>099-051800-
Western Mosquito Range/East Lake County Above 11000 Feet-
Leadville Vicinity/Lake County Below 11000 Feet-
Eastern Sawatch Mountains Above 11000 Feet-
Western Chaffee County Between 9000 and 11000 Feet-
Central Chaffee County Below 9000 Feet-
Western Mosquito Range/East Chaffee County Above 9000 Feet-
Saguache County West of Continental Divide Below 10000 Feet-
Saguache County East of Continental Divide Below 10000 Feet-
La Garita Mountains Above 10000 Feet-
Upper Rio Grande Valley/Eastern San Juan Mountains Below
10000 Feet-Eastern San Juan Mountains Above 10000 Feet-
Del Norte Vicinity/Northern San Luis Valley Below 8500 Feet-
Alamosa  Vicinity/Central San Luis Valley Below 8500 Feet-
Southern San Luis Valley-
Northern Sangre de Cristo Mountains Between 8500 And 11000 Feet-
Northern Sangre de Cristo Mountains Above 11000 Feet-
Southern Sangre de Cristo Mountains Between 7500 and 11000 Feet-
Southern Sangre de Cristo Mountains Above 11000 Feet-
Northwestern Fremont County Above 8500 Feet-
Western/Central Fremont County Below 8500 Feet-
Wet Mountain Valley Below 8500 Feet-
Wet Mountains between 6300 and 10000 Feet-
Wet Mountains Above 10000 Feet-
Teller County/Rampart Range Above 7500 Feet/Pikes Peak Between
7500 And 11000 Feet-Pikes Peak Above 11000 Feet-
Canon City Vicinity/Eastern Fremont County-
Northern El Paso County/Monument Ridge/Rampart Range Below
7500 Feet-
Colorado Springs Vicinity/Southern El Paso County/Rampart Range
Below 7400 Feet-Pueblo Vicinity/Pueblo County Below 6300 Feet-
Walsenburg Vicinity/Upper Huerfano River Basin Below 7500 Feet-
Trinidad Vicinity/Western Las Animas County Below 7500 Feet-
Crowley County-La Junta Vicinity/Otero County-
Eastern Las Animas County-Western Kiowa County-
Eastern Kiowa County-Las Animas Vicinity/Bent County-
Lamar Vicinity/Prowers County-Springfield Vicinity/Baca County-
1149 AM MDT Sat Aug 4 2018

This hazardous weather outlook is for portions of central...east
central...south central and southeast Colorado.

.DAY ONE...This Afternoon and Tonight

Isolated thunderstorms today will remain confined to areas in and
near the mountains. The primary storm threats are expected to be
lightning and wind gusts up to 50 mph. The threat for any heavy
rain or hail should be pretty low today.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

Isolated to scattered afternoon and evening thunderstorms are
expected each day. The primary concerns will be lightning, wind
gusts to 50 mph and locally heavy rain, though a few storms during
the period could be marginally severe, producing 60 mph winds and
quarter size hail. Area burn scars will continue to be at risk
for flash flooding during the period.

The best chance of thunderstorms will occur on Monday and Tuesday
as east surface winds force low level moisture up against the
eastern slopes of the eastern mountains. Storm activity both days
is expected to be more widespread, with a heightened potential for
flash flooding across area burn scars.

.SPOTTER INFORMATION STATEMENT...

Weather spotters will not be needed today or tonight.

12/12

Special Weather Statement
National Weather Service Pueblo CO
222 PM MDT SAT AUG 4 2018

COZ065-066-069-042045-
La Garita Mountains Above 10000 Ft CO-
Saguache County East of Continental Divide below 10000 Ft CO-
Del Norte Vicinity/Northern San Luis Valley Below 8500 Ft CO-
222 PM MDT SAT AUG 4 2018

...SIGNIFICANT WEATHER ADVISORY FOR SOUTH CENTRAL SAGUACHE COUNTY
UNTIL 245 PM MDT...

At 222 PM MDT, Doppler radar was tracking a strong thunderstorm 10
miles west of La Garita, or 42 miles northwest of Alamosa, moving
east at 15 mph.

Dime size hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
La Garita.

LAT...LON 3778 10653 3799 10649 3798 10619 3777 10625
TIME...MOT...LOC 2022Z 282DEG 12KT 3789 10644

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Special Weather Statement
National Weather Service Pueblo CO
237 PM MDT SAT AUG 4 2018

COZ065-066-069-070-042100-
La Garita Mountains Above 10000 Ft CO-
Alamosa  Vicinity/Central San Luis Valley Below 8500 Ft CO-
Saguache County East of Continental Divide below 10000 Ft CO-
Del Norte Vicinity/Northern San Luis Valley Below 8500 Ft CO-
237 PM MDT SAT AUG 4 2018

...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN RIO GRANDE AND SOUTH
CENTRAL SAGUACHE COUNTIES UNTIL 300 PM MDT...

At 237 PM MDT, Doppler radar was tracking a strong thunderstorm near
La Garita, or 35 miles northwest of Alamosa, moving east at 20 mph.

Dime size hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
Center and La Garita.

LAT...LON 3775 10646 3792 10640 3789 10605 3763 10614
TIME...MOT...LOC 2037Z 286DEG 19KT 3782 10635

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