Weather

280 
fxak67 pajk 062053 
afdajk 


Southeast Alaska forecast discussion 
National Weather Service Juneau Alaska 
1253 PM akdt Monday Oct 6 2008 


Short term... 
satellite imagery this morning is revealing a lot of 
cold air and convective activity out over the Gulf as well as a 
thin high cirrus shield that extends as far north as Frederick 
Sound. Lightning detection sensors are also reporting occasional 
strikes over coastal marine zones 51 and 52 as well as south of 
the Queen Charlottes. Have not seen any strikes yet over land but 
have included a mention of thunderstorm activity in the vicinity 
in the Yakutat taf. Radar is painting numerous cells offshore that 
are tracking north to northeast and synoptic data is indicating 
scattered to isolated showers over the southern Panhandle. To the 
north...Yakutat reported a rain snow mix earlier this morning. 


A front is forming off a weak low in the northern Gulf and is 
slowly tracking east as the low itself drifts north. The front should 
arrive over the coastal marine zones by tomorrow morning...so have 
a steady increase in probability of precipitation through the night becoming categorical 
over the entire outer coast and southern Inner Channels by 
tomorrow afternoon. Atmospheric instability over the marine zones 
will continue through tonight and into tomorrow. Built isolated to 
scattered thunderstorms into the afternoon marine forecast. 
Although the lifted index over the outer coast and southern Inner 
Channels is negative tomorrow afternoon...did not include any 
mention of thunderstorms over the Inner Channels or public zones 
because cape values do not look good enough to support them. 


Not a lot of wind in the forecast but do have small craft seas in 
the coastal marines zones which primarily reflects a SW swell 
moving into the northeast Gulf. 


Overnight lows are once again going to be in the low to middle 30s 
from Icy Strait north so will likely issue frost advisories for 
zones 17 through 21 as well as for Juneau for tonight. No snow in 
the public forecast but snow levels are getting lower. A rain snow 
mix is possible for Yakutat tonight but the chance for snow in 
other northern inner zones tonight will be offset by low probability of precipitation. 


Long term... 
large scale trough over the Gulf will move east across the Panhandle 
Wednesday bringing showers with it. Plenty of cold air over the Gulf 
will accompany the trough...bringing cooler temperatures Wednesday night/Thu. 
A ridge will build in behind the trough Thursday allowing for a brief 
reprieve from the shower activity. 


A 970 mb low over the central Aleutians Wednesday makes its way east and 
weaken to 980 mb over Kodiak Island early Sat morning. The 
associated front will move across the Gulf Friday bringing gales 
to the outer waters and southern straits and passages. 


Models still in good agreement through early Sat. GFS remains the 
most consistent of the model solutions. Overall...not making any 
major changes to the grids. Will refresh them with the 10/12z GFS 
run. 


&& 


Ajk watches/warnings/advisories... 
public...none. 
Marine...Small Craft Advisory for pkz041>043-051-052. 


&& 


$$ 


Fritsch/mam 

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