545 
fxus65 kpih 071951 
afdpih 


Area forecast discussion 
National Weather Service Pocatello Idaho 
200 PM MDT Thursday Aug 7 2008 


Discussion...latest satellite/radar imagery showing active 
convection moving across the central mountains early this afternoon 
with a trailing line extending south-southwest to Jackpot. Area expected to 
progress NE late this afternoon and will continue with some 
scattered mention of convection across the forecast area this 
evening due to proximity of monsoonal moisture to the south...an 
increase in low level dew point temperatures and passing weak waves aloft. 
Models have been keying on a broader scale wave currently positioned 
off the central California coast which is expected to kick inland 
tonight and Friday providing the impetus for organized convection 
across the central mountains Friday afternoon. Cells should make good 
progress with 15kt steering flow out of the SW. Best precipitable water/S (around 1 
inch) were located closer to the Utah border with 0.75+ over the 
central mountains. With organized storms Friday...will be expecting 
decent precipitation returns although it remains to be seen if any 
will produce flash flooding. Thus will allow Flash Flood Watch 
currently in effect for the burn areas across the central mountains 
for Friday to continue. Wave exits to the NE Friday night as 
main/parent low off the northwest coast begins to swing east into the 
British Columbia coast by Saturday noon and then slowly east across 
western Canada Sunday/Monday as drier...cooler...more stable airmass 
overspreads the region early next week. Upper ridge rebounds across 
the region beginning Tuesday and continues through at least middle-week 
with temperatures gradually warming under stable conditions. 
GFS/European model (ecmwf) appear to be at odds by middle-week with GFS driving next 
system inland across the northern Great Basin Thursday night/Friday 
whereas the European model (ecmwf) allows it to flounder off the northern California 
coast. Will maintain current dry forecast until we can get another 
couple of model runs under our belt. Huston 
&& 


Aviation...moist air continues to push north into Idaho. Expect 
VFR conditions but have thunderstorms through early evening at taf 
sites. Think Hailey most likely to see a thunderstorm on station. 
But all sites will be under the threat. Expect scattered 
thunderstorms through Saturday. Gk 
&& 


Fire weather...monsoonal moisture remains in place over southeast 
Idaho with mainly wet thunderstorms expected through Saturday. Red 
flag warnings remain in effect until midnight tonight in zones 
412...475...476 and 477 due to scattered coverage of the 
thunderstorms. Extensive lightning pushing into 475..476 and 477 
early this afternoon. Red flag warnings due to thunderstorms may 
need to be repeated Friday and Saturday with expected scattered or 
greater coverage to continue. Gk 
&& 


Pih watches/warnings/advisories... 
red flag warning continues through midnight tonight for 
idz412-475>477. 


Flash Flood Watch continues for Friday afternoon through Friday 
evening for idz018-031. 
&& 


$$