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Area forecast discussion 
National Weather Service Pueblo Colorado 
334 PM MDT Thursday may 23 2013 


Short term...(this evening through friday) 
issued at 244 PM MDT Thursday may 23 2013 


..some severe potential parts of the plains next 24 hours... 


Cool...stable airmass has covered the plains most of today...keeping 
temperatures well below average. Meanwhile...windy and warm to the 
west of the southern Front Range. Some elevated convection breaking 
out across the southern San Luis valley...southern sangre Delaware cristos 
and southern foothill areas...with maybe even a cell trying to form 
on the southwest Baca County border. Expect this activity to 
continue and increase a bit this evening. Then...overnight...mainly 
after midnight...still some isolated to scattered showers possible 
mostly light stuff...but could even be some embedded convection which 
could drop some heavier precipitation on a local basis. Continued 
mainly dry west of the southern Front Range overnight. 


On Friday...could be some severe storms over the far southeast 
plains late in the day...generally after 3 PM MDT. Dryline will 
be out there somewhere...probably running southwest to northeast 
across Baca...Prowers and Kiowa counties. Shear is low initially 
but eventually creeps up to around 40 or 45 knots along the Kansas 
border by late in the day. So...could be a few severe cells to 
deal with. Large hail would be primary threat...but there is more 
than enough cape...and sufficient shear...that a tornado cannot be 
ruled out either. 


Other concern tomorrow will be the fire danger. Looks like 
winds...humidities and fuels will all be at critical levels tomorrow 
afternoon...so hoisted a Fire Weather Watch for the all of the 
eastern mountains...including Teller and El Paso counties. Outdoor 
burning or any other activities that could start a fire should be 
suspended. Lw 


Long term...(friday night through thursday) 
issued at 244 PM MDT Thursday may 23 2013 


Friday night and Saturday...an upper low will spin over the 
Pacific northwest while high pressure sits over the Central 
Plains. Continued southwesterly flow will persist across The 
Rockies with weak embedded energy. Expect thunderstorm activity to 
be ongoing over the far eastern plains Friday evening. Instability 
and shear will be supportive of at least strong and possibly a 
couple of severe storms through 9pm Friday evening. Damaging 
winds and large hail are possible. Expect all activity to shift 
east into western Kansas through midnight with dry conditions into 
Saturday morning. The main forecast challenge for Saturday will be 
the position of the dryline which will determine if and where 
thunderstorms will develop. Current solutions have the dryline set 
up from the northeast corner of Kiowa County...southwest to near 
Springfield. Have isolated thunderstorm activity in the forecast 
east of this line. Given the shear and instability...they could be 
strong to severe. This will need to be monitored since any shift 
in the dryline could lead to more widespread coverage across the 
eastern plains...or none at all. On the west side of the dryline 
expect low humidity values and gusty southwesterly winds. This 
will lead to critical fire weather conditions for the western half 
of the County Warning Area...and any fire weather highlights will depend on fuel 
status. Extreme caution is advised over this area on Saturday. 


By Sunday the low begins to break down with broad troughing 
expected over the western Continental U.S.. this will enhance southwesterly 
flow aloft across the region and force the ridge into the Missouri 
Valley. This will help push the dryline well into Kansas for both 
Sunday and Monday helping to mitigate any thunderstorm chances for 
southern Colorado. Gusty southwesterly winds and low humidity 
values will keep dangerous fire weather conditions across all of 
southern Colorado. Extreme caution is advised for any outdoor 
burning activities...including backyard grilling on Memorial Day. 
Temperatures will remain warm with upper 80s to middle 90s for highs 
across the lower elevations. 


The upper trough shifts east Tuesday into Thursday into Colorado. 
This will bring slightly cooler temperatures to the area with 
generally 80s through the middle of the week. This will also bring 
enhanced chances for shower and thunderstorm activity to the 
mountain areas...especially the Continental Divide. Mozley 


&& 


Aviation...(for the 00z tafs through 00z Friday evening) 
issued at 244 PM MDT Thursday may 23 2013 


MVFR to LIFR stratus and patchy fog has been persistent over the 
eastern mountains and plains today...but has finally broken up for 
the most part. A few evening -shra and -tsra are possible through 
about 04z this evening. Then...overnight areas of at least MVFR 
stratus will redevelop and cover both the kcos and kpub terminals 
until middle-morning Friday. At kals...expect VFR conditions through 
Friday. Lw 


&& 


Pub watches/warnings/advisories... 
Fire Weather Watch from Friday afternoon through Friday evening 
for coz221-222-225>227. 


&& 


$$ 


Short term...lw 
long term...mozley 
aviation...lw