Special Weather Statement, NWS Pueblo, CO

Area Forecast Discussion
National Weather Service Pueblo CO
228 PM MDT Sat Aug 25 2018

.SHORT TERM...(This evening through Sunday)
Issued at 222 PM MDT Sat Aug 25 2018

Currently, isolated to scattered thunderstorms have developed across
the high terrain, with greatest thunderstorm coverage over the
southern Sangre's and adjacent plains. A few isolated showers have
also developed across portions of the eastern plains, south of HWY
50. Storms are developing in response to a series of disturbances
lifting northeast per GOES-16 water vapor imagery: one currently
over northeast New Mexico and another over northeast Arizona. Broad
high pressure is situated over eastern Texas, causing southwest flow
aloft over Colorado. TPW's are slowly increasing over southern
portions of the CWA to near/just above normal levels. Cloud analysis
over the plains using GOES-16 1-min imagery indicates
destabilization has taken place across the plains south of HWY 50,
with areas north still stable. Temperatures across the plains and I-
25 corridor span the upper 80s through the 90s, and 70s in the high
valleys

Rest of today and tonight, showers and thunderstorms are forecast to
persist in the mountains through early evening, before mostly
dissipating by midnight as the mid-level energy continues to lift
northeast and the atmosphere stabilizes. For the plains,
thunderstorm will continue to expand east through the late afternoon
and early evening, before mostly dissipating/moving into Kansas by
around midnight. Thunderstorms will remain weak in most areas
considering weak instability and shear. The threat for a strong
storm or two will be greatest across the far eastern plains, where
effective shear is/will be 25-30 knots, and MLCAPE around 1000 j/kg,
per SPC mesoanalysis. The greatest storm threat appears to be flash
flooding potential over burn scars. In general, though , storms
shouldn't be producing too much rainfall over any given location
considering not-outrageous TPW and the fact that storms are moving
at a decent pace. Further east, storms could produce hail less than
1 inch in diameter and wind gusts to 50 mph. Low temperatures this
evening are expected to be in the low to mid 60s across the plains
and Colorado Springs, and mid to upper 40s in the high valleys. Mid
to high clouds will persist through much of the evening before
dissipating by the morning. Low clouds are possible in the San Luis
Valley by early morning considering light winds and today's rainfall.

Tomorrow, high pressure is forecast to remain centered southeast of
Colorado, leading to continued west to southwest flow over Colorado.
Disturbances in the flow are expected to be weaker, and along with
slightly less moisture compared to today, should lead to less
thunderstorm coverage for Sunday. Isolated to widely scattered
storms will develop over the high terrain, especially the southwest
mountains, during the late morning/early afternoon under intense
heating, and will quickly move east. Only a storm or two is expected
to make it into the I-25 corridor, with the rest of the eastern
plains more likely remaining dry. Although effective shear will be
more favorable considering the upper level jet moving over Colorado,
instability will be weak so thunderstorms are expected to remain sub-
severe. Sunday will be hot, with highs in the mid 90s across the
plains, upper 80s in Colorado Springs, and low to mid 80s in the
high valleys.

.LONG TERM...(Sunday night through Saturday)
Issued at 222 PM MDT Sat Aug 25 2018

A weak disturbance will be exiting the area Sun evening and most, if
not all precip chances should end by about midnight.  Dry westerly
flow over the area on Mon is expected to bring dry weather with high
temps that are 5-10 degrees above average.  It may be breezy enough,
and dry enough to have some fire weather concerns in a few areas Mon
afternoon.

Mon night, a disturbance passing to the north of CO will send a
front thru the eastern CO plains early Tue morning. In the wake of
the front, there could be some low clouds over portions of the
southeast plains, especially in areas near the KS border. The
passage of the front will bring north surface winds to the area
early in the day, and then the winds will become easterly in the
afternoon. At this time, the forecast models keep the area dry
thru Tue afternoon, with the GFS then showing the potential for a
few showers/tstms along some of the eastern mtns in the evening
hours. High temps across the southeast plains on Tue will probably
be at least 10 degrees cooler than on Mon, but will still be
around or a little above average in the high valleys.

On Wed an upper ridge will be centered to the south of CO, with
westerly flow aloft over southern CO.  However, southerly surface
winds over the far southeast plains are expected to bring higher dew
point air to that area.  The GFS shows dew points in the upper
50s/lower 60s in the afternoon/early evening hours.  Most of the
area is expected to be dry Wed, but the GFS shows a little precip
along some of the eastern mtns, with a better chance for precip
over the far southeast plains.

Relatively dry westerly flow aloft is expected over the area on Thu
and into early Fri, with maybe just some isolated precip over some
of the mtns and southeast plains.  Fri afternoon a disturbance moves
across the state, bringing an increased chance for showers/tstms
over the mtns and eastern plains from about mid-late afternoon thru
the evening, and possibly continuing thru the night over the
southeast CO plains.

The upper ridge is forecast to build over the area Sat, bringing dry
weather to southern CO.

&&

.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 222 PM MDT Sat Aug 25 2018

Isolated to scattered thunderstorms will persist into the early
evenings over the higher terrain of southern Colorado, and parts of
the plains. KALS and KCOS should see showers and thunderstorms in
the vicinity of the terminal through the early evening. KPUB has
more limited potential to see an isolated shower or thunderstorm
late this afternoon/evening, but confidence is low in this
happening. Thunderstorms will develop again over the high terrain by
late Sunday afternoon, but should stay away from the three terminals.

KPUB and KCOS should be VFR for the next 24 hours with mid to high
level cloud cover. KALS could see reduced CIGs/VIS late
tonight/early Sunday morning with fog and low cloud potential
(confirmed by some Bufkit soundings), especially if the area
receives rainfall.

&&

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

SHORT TERM...LINE
LONG TERM...28
AVIATION...LINE

Hazardous Weather Outlook
National Weather Service Pueblo CO
1205 PM MDT Sat Aug 25 2018

COZ058>089-093>099-261815-
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-
1205 PM MDT Sat Aug 25 2018

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

.DAY ONE...This Afternoon and Tonight

Scattered to widespread showers and thunderstorms are expected this
afternoon over the mountains, spreading east across the plains by
this evening and overnight. Locally heavy rainfall, lightning,
gusty outflow winds to 50 mph and half inch hail will be possible
with stronger storms. If a stronger storm can move across a burn
scar, flash flooding will be possible. Expect showers and
thunderstorms to come to an end during the overnight hours.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

On Sunday, isolated to scattered afternoon and evening thunderstorms
are expected, mainly over the mountains.  The primary weather
threats will be lightning, gusty winds and locally heavy rainfall.

Wednesday through Friday, spotty afternoon and evening thunderstorms
will be possible.  The main weather threats will be lightning and
gusty winds.

.SPOTTER INFORMATION STATEMENT...

Weather conditions that meet reporting criteria for spotters will be
possible this afternoon and tonight across the mountain areas, burn
scars and eastern plains.

12/12

Special Weather Statement
National Weather Service Pueblo CO
349 PM MDT SAT AUG 25 2018

COZ093-095-097-252215-
Las Animas Vicinity/Bent County CO-Western Kiowa County CO-
La Junta Vicinity/Otero County CO-
349 PM MDT SAT AUG 25 2018

...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN OTERO...SOUTHWESTERN
KIOWA AND NORTHWESTERN BENT COUNTIES UNTIL 415 PM MDT...

At 349 PM MDT, Doppler radar was tracking a strong thunderstorm 8
miles east of Cheraw, or 13 miles northeast of North La Junta, moving
northeast at 15 mph.

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

Locations impacted include...
Blue Lake and Arlington.

LAT...LON 3801 10329 3803 10340 3835 10335 3825 10309
TIME...MOT...LOC 2149Z 204DEG 14KT 3811 10336

28