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Area forecast discussion...updated 
National Weather Service Pueblo Colorado 
1129 am MDT Friday Jul 18 2008 


Update... 
just a quick update to increase probability of precipitation over the high terrain. Some 
concern for plume of moisture coming up from northwest New Mexico. 
Seeing some lightning over southern sangres. Expect to see 
lightning vicinity Pikes Peak by noon. Coverage should increase across 
the Pikes Peak region this afternoon as Utah short wave 
approaches. 




Aviation... 
thunderstorms will develop over mountain areas including Pikes 
Peak with coverage increasing to scattered by 20z. Isolated heavy 
rain and low visibility vicinity thunderstorms over mountains. 


&& 


Previous discussion... /issued 334 am MDT Friday Jul 18 2008/ 


Short term... 


(today and tonight) 


C51enges are chances for showers this morning...temperatures and 
coverage of precipitation this afternoon and evening. 


Currently...water vapor imagery shows deep moisture has exited into 
panhandles and Kansas. Good deal of middle and upper level moisture 
over County warning forecast area. Shortwave appears to be over western Utah...with slug of 
moisture in eastern Arizona moving north northeastward. More clouds 
than clear over County warning forecast area at this time. Dew points in the upper 50s to lower 60s 
across the eastern...with 30s to lower 50s in the west. 


Today...nam12 looks to be overdoing quantitative precipitation forecast this morning. Guidance and 
surrounding offices sticking with isolated to scattered probability of precipitation...so 
will maintain broad brush isolated probability of precipitation through the morning. With 
good deal of moisture...and pot vorticity lobe approaching...along with 
moisture from the south southwest...seems wise to keep scattered 
showers and thunderstorms for all areas this afternoon. Cape values 
not that exciting...below 1000 j/kg...and best shear over northeast 
Colorado (our values maximum out at 25 kts). Storm Prediction Center outlooks northeast 
Colorado...but not quite into our County warning forecast area...which looks right on. Feel 
even pulse severe storms unlikely over our County warning forecast area...although not 
impossible. Isolated heavy rain probable with slow movement of the 
stronger storms. High temperatures will be tough...given wild card 
of cloud development and scattered rains. Met guidance seems to be 
too high...so basically went with mav guidance. Going forecast 
accepted with 80s across the plains...70s and 80s high valleys...and 
60s and 70s mountains. 


Tonight...isolated to scattered probability of precipitation seem reasonable up until 
midnight...as advertised by nam12. Strong to severe convection 
northeast of our County warning forecast area...will probably send some outflow boundaries 
into our County warning forecast area...which would keep the rain chances going in the 
plains through late evening...along with the possibility of a couple 
near severe storms. Models show ridge building into Colorado 
overnight...with good drying aloft and some at the surface. Skies 
clear out nicely in the northern County warning forecast area...and less so in the south. 
-Tlm- 


Long term... 


(sat-thu) 


.Hot this weekend then temperatures cooling a bit for next week... 


It is simply going to be hot and dry this weekend across the region. 
All guidance showing a dominating middle level ridge developing over the 
area which will allow temperatures to easily get into the 100s 
across most if not all of the lower Arkansas River valley. Elsewhere 
it will be hot with highs in the 90s across the kcos region...with 
80s in the valleys. Precipitation will be hard to come by as flow at middle 
levels (northerly) combined with the subsidence will keep it dry. 
The best chance of precipitation will be over the SW mountains I should note 
that GFS by Sunday is a bit more optimisitic on pushing the high to 
the east and this may allow for some moisture to work in from the 
south and into central Colorado...but this may be optimistic. For 
now I kept the mountains on the drier side. 


By next week...the ridge will be shunted to the east and we should 
start to get more of a S component to the winds in the lower 1/2 of 
the atmosphere. This should allow temperatures to cool a bit (but still 
will be a few degrees above climo) and allow moisture to work up 
from the S increasing the chances for precipitation...especially in the 
mountains additionalyly...guidance is also hinting at a boundary working 
south by middle week which should help cool down the plains and may 
increase the chance of precipitation over the plains. \/34 


Aviation... 


Thunderstorms will be isolated to scattered across the area this 
afternoon and evening...and will be near or occur at the three taf 
sites...with the most likely target for occurrence kcos. Brief MVFR 
conditions would occur with stronger storms. After convection 
wanes...sky cover should decrease late evening into Saturday 
morning. Low clouds in the morning seem unlikely at this time. -Tlm- 


&& 


Pub watches/warnings/advisories... 
none. 
&& 


$$ 


21/17