FXAK67 PAJK 182223
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
223 PM AKDT Sat May 18 2019

.SHORT TERM.../Through Sunday night/...Low impact short range 
forecast period. A low over the central Gulf will continue to move
off to the northwest while slowly weakening. Precipitation 
associated with a weak frontal feature will continue to rotate 
around the low and remain mostly offshore tonight or on the 
immediate outer coast this evening. By Sunday morning, a 
developing surface trough will then rotate around the same low. 
Heaviest precipitation associated with this trough will also 
remain mostly offshore, but lighter amounts are expected along the
outer coast north of Cape Decision from tomorrow afternoon and 
lasting through Sunday night. 

Small craft conditions on the outside for winds and/or seas. 15 kt
winds or less on the inside. Partial clearing of the skies is
expected mostly during the overnight hours with mostly cloudy
conditions during the day. Thus, daytimes highs will be a little
subdued while radiational cooling at night will be aided. 
However, daytime highs will be warm enough that freezing temps at 
the surface not expected. 

Updated pressure with GFS to move the developing surface trough
around the low a little faster. PoP a blend of GFS, NAM, and SREF.
QPF from NAM and GFS. Overnight lows for Saturday night adjusted
per the National Blend. Remaining temps unchanged. Overall
forecast confidence is average. 


.LONG TERM.../ Monday to Saturday as of Friday evening / The early
part of the mid range forecast are in fair agreement. An area of
low pressure southwest of Kodiak Island a much stronger nearly
vertically stacked low is moving slowly east across the Pacific 
towards the Oregon coast from Sunday to Monday evening. Over
northwestern Canada a high aloft will hold in place, and will keep
the flow pattern from becoming progressive and most of the flow
moving more north rather than east. The jet stream is quite zonal
across the Pacific with a 170+ kt core that is headed to towards
north central California by Tuesday. The jet core will start to
deepen a trough along the west coast of the CONUS and as a result
build a ridge northward into the central and eastern gulf. 

The building ridge aloft through mid week will force the remains
of the through aloft that had been over the eastern gulf through
the panhandle and should result in the potential for light rain
around Wednesday to Thursday. 

On the west side of the building ridge a stronger southwest flow
for the Thursday to Friday and early next weekend potentially. 
This will lead to a wetter pattern over the northern panhandle 
for the end of the week. 

Long range details are still a little chaotic looking from one
model solution to the next, however, they are starting to align as
they move a little closer to the mid range. Edits at the long
range leaned towards the ensemble method of the WPC solution. Only
needed to make some minor wind directional edits, and the 
temperature forecast from Thursday onward got a minor reduction 
with more clouds under what looks like a good southwest flow 
pattern of clouds and likely rain. 

&&

.AJK Watches/Warnings/Advisories...
PUBLIC...None.
MARINE...Small Craft Advisory for PKZ042-043-051-052. 
     Small Craft Advisory due to Seas for PKZ041. 

&&

$$

Fritsch/Bezenek

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