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fxus65 kpub 062126 
afdpub 


Area forecast discussion 
National Weather Service Pueblo Colorado 
326 PM MDT Monday Oct 6 2008 


Short term... 
(tonight and tuesday) 


Precipitation has ended over the eastern plains as upper low pulls slowly 
away into the Central Plains. Moderate north to northwest winds have 
surfaced over much of the area this afternoon...but these should die 
off quickly this evening as surface gradient is very weak after 00z. 
Expecting shallow convective cloud deck to quickly clear out this 
evening as well...as downward motion continues. Frost potential 
tonight the main question...as surface dewpoints have already 
fallen into the 20s along the I-25 corridor...with 30s to near 40 
holding on farther east. Guidance argues for temperatures staying in the 
middle to upper 30s...but given current state of the air mass...suspect 
the usual cold spots (i.E. Arkansas valley) will see some frost due 
to fairly well developed cold air drainage winds by morning. Farther 
east...just enough rain last night to hold dewpoints up a few 
degrees...so will limit frost advisory to just the I-25 corridor. 
Fine fall day on Tuesday...with mild temperatures and light winds. 


Long term... 
(tuesday night through monday) 


..unsettled weather again this weekend... 


Tuesday night through Thursday...models still persist in keeping the 
Flat Ridge over the desert SW...with near zonal flow across the 
rocky Montana region. Ongoing forecast grids have warm temperatures and dry 
conditions...and this looks good. NAM does indicate a dry cold front 
dropping down the east plains late Wednesday morning...which could 
potentially cool maximum temperatures a bit Wednesday. For now...maximum temperatures in the middle 
70s seems reasonable. Thursday the flow aloft shifts a bit to the 
SW...and continued temperatures in the 70s to near 80 look alright as well. 


Friday through Monday...it needs to be stressed that there is a lot 
of uncertainty for the weekend. Long range models are wavering on 
possible solutions...and it seems every model run presents something 
different. However...the European model (ecmwf) has now been consistent for two to 
three runs...so starting to lean towards that model as well as some 
of the surrounding offices. The European model (ecmwf) digs the incoming trough deep 
into Nevada and California Friday...spreading precipitation across western Colorado. By Sat afternoon 
the closed lopw is ejecting up across Utah into S Idaho with precipitation 
continuing across all of the mts and high valleys. Sun the low 
proceeds across Wyoming and Montana...finally spreading some precipitation to the 
Palmer dvd and perhaps far east plains. However...much of the eastern 
plains remain dry and warm from downslope flow. By Monday the system is 
gone into Canada...with northwest flow aloft then settling in across the 
state. This scenario is not a particularly cold one...and is more of 
a strong wind and Montana snow storm while the plains once again get 
neglected. This is the solution that the grids are leaning 
to...however this far out there is plenty of time for the models to 
fluctuate. 


Will quickly mention the latest GFS solution...which places the 
upper low closer to the 4 corners before slowly ejecting it across 
Colorado. This would mean much colder temperatures and more widespread 
precipitation. Again...this is not the direction the forecast is heading 
necessarily...but there are differing and rapidly changing solutions 
out there. Moore 


&& 


Aviation... 
gusty north winds should fade away quickly by sunset as mixing ends. 
Few ac over the area should dissipate this evening as well...with 
clear skies and light drainage winds all taf sites overnight. Clear 
skies and light diurnally driven winds expected on Tuesday. 


&& 


Pub watches/warnings/advisories... 
frost advisory from midnight tonight to 9 am MDT Tuesday for 
coz083>088. 


&& 


$$ 


10/27