219 
fxak68 pafc 191207 
afdafc 


Area forecast discussion 
southcentral and southwest Alaska 
407 am akdt Friday Mar 19 2010 


Analysis and upper levels... 
broad upper level blocking high pressure ridge resides over much of 
the interior...confining much of the significant weather to the 
Bering Sea or the Gulf of Alaska. A large trough encompasses much of 
the Bering while an embedded vertically stacked low is rotating into 
the north central Gulf and weakening significantly. At the 
surface...a new surface low is taking shape in the Gulf near the 
triple Point of the current frontal system...located 300 miles east 
of the current low. The occlusion has pushed inland over the northern 
Gulf Coast...bringing rain and snow to much of Prince William Sound 
and the western Kenai Peninsula and clouds to the rest of south 
central Alaska. Further west...a snowy frontal system is pushing 
slowly eastward across the eastern Bering Sea and the akpen. 


Model discussion... 
models are doing a decent job in depicting the large scale weather 
features across most of the aor...with the Gulf region proving to be 
the one exception. The NAM is the only model depicting the 
aforementioned new triple point low developing in the eastern Gulf 
while the GFS and European model (ecmwf) leave this system as an open wave. Thankfully 
the models generally agree on the track and demise of the Gulf low 
over the next 24 hours. The European model (ecmwf) is much more aggressive with the 
strength and speed of a series of lows that track into the Gulf on 
Sunday and Tuesday. 


Short term forecast... 
south central Alaska...the current Gulf low pushes north and 
gradually dissipates as it makes landfall along the Kenai Peninsula 
on Friday night. Widespread precipitation will persist through 
Saturday morning along the Gulf Coast. Little to no precipitation is 
expected from this storm in the Anchorage area with easterly 
downsloping winds well established. The weekend looks pleasant for 
the Anchorage area and the mat-su valley...with temperatures holding 
steady and clouds diminishing on Saturday. 


Southwest Alaska...the remnants of a frontal system pushing slowly 
but steadily across the eastern Bering will make landfall over 
western Alaska later today. Snow showers associated with the 
disturbance will linger over the region through Saturday...but 
overall snow accumulations should be minimal. 


Aleutians and Bering Sea...a series of quick shortwaves clip the 
western Aleutians over the weekend and spread light showers over the 
western Bering. A low tracks well south of the central Aleutians on 
Sunday...though it may spread some light precipitation over the 
central portion of the island chain. 


Long term forecast... 
relatively quiet weather remains in store for the beginning of next 
week. A new frontal system works across the western Aleutians/Bering 
Sea on Tuesday before running up against a east Bering ridge and 
dissipating. A low rotating into the Gulf on Wednesday will bring 
another round of precipitation to the northern Gulf Coast. 
Temperatures should cool down slightly as northerly winds set in out 
ahead of this low...but nothing like the cold weather the region saw 
a week ago. 




Aer/alu...watch/warning summary 
public...none. 
Marine...Gale Warning...125 127 130 172. 
Storm Warning...120. 
Fire weather...none. 


Kansas Mar 10 

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