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fxus65 kvef 211102 
afdvef 


Area forecast discussion 
National Weather Service Las Vegas Nevada 
402 am PDT sun Mar 21 2010 


Synopsis...high pressure will continue over the area on Sunday 
before being moved east on Monday by the next low pressure system 
moving into the Pacific northwest. Afternoon high temperatures on 
Sunday and Monday will be about five degrees above normal. The next 
storm system will move into Utah on Tuesday bringing cooler 
temperatures to the area and a slight chance of precipitation to the 
higher elevations across southern Nevada and northwestern Arizona. 
High pressure will return to the area middle week warming afternoon 
temperatures back above normal. 




&& 


Short term...today through Tuesday night. 
Short term models are now in excellent agreement and this 
forecast will be a blend. High pressure across the area today will 
be moved east tonight as a low moves into the Pacific northwest. 
The main low tracks north of the forecast area on Monday and moves 
into Utah on Tuesday. An upper level low approaches Southern 
California/northern old Mexico on Tuesday. This combination will 
cause gusty north wind across the forecast area on Tuesday. Once 
again will continue to watch this situation. The model are not 
indicating the winds to be that strong...but the system does not 
look all that different from the system that came through a few 
days ago. 


Afternoon high temperatures will be five plus degrees warmer today 
than on Saturday. Despite the approaching trough...temperatures on 
Monday will be even warmer than today due to southwest winds and 850 
temperatures warming a few more degrees. Behind the front 
temperatures will return to normal for this time of year. 


There is not much moisture with the system on Tuesday. The best 
chance for precipitation will be for the higher elevations of 
Lincoln and Mohave counties. 


Long term...the Tuesday low is forecast to be over The Four Corners 
Wednesday morning and dry conditions are expected on Wednesday as 
ridging builds over the area. This will likely give a boost to 
temperatures and about 5 degrees of warming is expected over 
Tuesday. The ridge axis slides east and zonal flow is forecast over 
the region Thursday. Temperatures should remain flat and average 
about 5 degrees above normal. A shortwave moving towards the area 
for Friday/Friday night could bring an increase in wind and slightly 
cooler air. However... there is model disagreement with the 
strength...timing and track of the system with the GFS solution weak 
and fast and the European model (ecmwf) slower and stronger. The gefs members support 
a somewhat stronger solution than the operational GFS and basically 
splits the difference between the 00z GFS and the 00z European model (ecmwf). Decided 
to hold off on any major grid changes due to the uncertainty but 
slightly cooler and breezy conditions are not out of the question 
for Friday into early Saturday. The weekend itself looks pleasant as 
high pressure is forecast to move in and temperatures respond by 
warming 5-10 degrees above normal. Models then develop a longwave 
trough over the Gulf of Alaska beyond next weekend. This could 
potentially send a series of progressive shortwave systems our 
direction to end March. Too early to say for sure but just a heads 
up. 


&& 


Aviation...for McCarran...winds will follow diurnal directional 
trends today...southwest at night and northeast during the day. 
Varying amounts of cirrus expected today. A system dropping out of 
southwestern Canada will bring increasing southwest winds to the 
area Monday and north winds behind a cold front early Tuesday. 


For the rest of southern Nevada...northwest Arizona...and southeast 
California...light winds generally under 10kts area wide today except 
in kdra where southwest winds could increase to 10-15kts. Southwest 
winds to become more prevalent on Monday as a system drops out of 
southwestern Canada and then northerly behind a cold front Monday 
night and Tuesday. Skies will have varying amounts of high clouds 
today. 




&& 


Vef watches/warnings/advisories... 
Nevada...none. 
Arizona...none. 
California...none. 
&& 


$$ 


Borden/Salmen 


Http://weather.Gov/lasvegas