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fxus65 kbou 212019 
afdbou 


Area forecast discussion 
National Weather Service Denver Colorado 
210 PM MDT Thursday Aug 21 2008 


Short term...slight warm advection in the middle troposhere should 
cap convection today...we will continue with a dry forecast. On 
Friday cold front will move through by midday...undercutting the 
warm air aloft. Low level air coming in during the afternoon will be 
cooler with more moisture...but should still be stable. Combination 
of increasing moisture and the reversal of todays warming aloft will 
likely not be enough for thunderstorms...but I will leave small probability of precipitation 
over the mountains and Palmer Divide late in the day. Still plenty 
of sun so not a lot of cooling...current forecast of middle 80s looks 
good. 


Long term...once the cool front moves into the County warning forecast area...Ely winds will 
allow low level moisture to increase with precipitable water values climbing back 
over 1 inch. Forecast soundings show the air mass should remain capped for the 
most part with a warm layer between 700 mb and 550 mb. Best 
potential for thunderstorms will be along the foothills and possibly the far 
eastern plains. Will keep probability of precipitation going mainly in these areas but will go 
with isolated coverage. For Saturday...instability increases across the 
area as low level moisture will combine with warmer afternoon temperatures. Precipitable water 
values still over an inch so storms will produce locally heavy 
rainfall. Similar conditions will occur on Sunday. Drier air mass can be 
expected by early next week as the upper ridge starts to build over 
the west. The next system is prognosticated moves across Colorado by Thursday as 
it drops out of the northern rockies. The trough appears fairly 
progressive so overall not much qpg generated by the models with a dry 
northwest-westerly flow aloft over the state. Will stick with slight chance probability of precipitation for 
the rest of next week. 


&& 


Aviation...VFR conditions are expected through Friday. There is a 
slight chance of high based thunderstorms late Friday afternoon. 


&& 


Bou watches/warnings/advisories...none. 


$$ 


Gimmestad/Cooper