Area Forecast Discussion
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000 FXAK67 PAJK 242252 AFDAJK Southeast Alaska Forecast Discussion National Weather Service Juneau AK 252 PM AKDT Sat Mar 24 2018 .SHORT TERM...
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A late season snow event is possible for the northern Panhandle in the short term. Saturday afternoon begins with a weak low over the north central gulf and some shower activity associated with it. This low will drift southeast over the next 24 hours. The more interesting system arrives behind it with a weather front passing over the Panhandle Monday. Cool temperatures over the panhandle especially the northern Panhandle will allow for a late season overrunning snow event for the Panhandle on Monday. The model trend with this system has been slower with each new model run; therefore, most of the snow over the northern Panhandle is likely during the Monday afternoon and evening hours. A warm up is expected behind the front so a transition to rain sooner than forecasted is still possible, which would limit snowfall totals. Not many changes were made to the short term forecast. Gales were introduced over the northern gulf on Monday along the front. In addition, with newer guidance pushing more precipitation north, QPF was increased over the central and northern zones. A fair number of models currently carry more snow than what is the forecast for the Juneau area Monday night. These totals would support higher end advisory or possibly warning level snow totals in the Juneau area on Monday night, but confidence is lower in this timeframe with models still struggling on run to run consistency. The current forecast represents the lower end of possible snowfall totals with 3 to 5 inches of storm total snow for the Juneau area Monday Evening. .LONG TERM.../Sunday afternoon through Friday as of 10 PM Friday/Changes in the long term forecast were focused on the Sunday afternoon through Monday timeframe, with newer model runs causing a shift in thoughts on the mid-range forecast. Sunday afternoon begins with a weather front orientated along a NW to SE axis over the gulf. It will track northeast through Monday with precipitation likely beginning over the Southern Panhandle first, late Sunday night. Precipitation will begin primarily as snow or a rain snow mix for much of the Panhandle before transitioning to rain over the southern Panhandle. Due to the orientation of the front the Northern Panhandle will remain in a northerly wind pattern keeping cooler air around longer and allowing snow to persist through much of Monday. Areas that look to receive the most snow out of the system are the Juneau, Haines, Skagway, and Yakutat areas all of which are carrying between 3 and 5 inches of snow over the course of the day Monday. The front will eventually advect warm air into the panhandle bringing Tuesday`s high temperatures up considerably compared to Monday. Toward the middle of the week another low pressure system will form over the southern gulf and track northeast across it. Model agreement with the Sunday to Monday front has improved from the previous day. Changes were focused on keeping winds northerly longer as the front comes in over the the northern Panhandle. This in turn keeps the cooler air in place longer and decreased temperatures from the upper 30s to the low 30s on Monday over the northern Panhandle. Snow levels in turn were decreased as well allowing more snow than the previous forecast. Run to run consistency beyond the Monday system has been sub-par causing the rest of the extended forecast to be left as is until confidence has increased enough to make relevant changes.
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&& .AJK Watches/Warnings/Advisories...
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PUBLIC...None. MARINE...Gale Warning for PKZ013. Small Craft Advisory for PKZ012-022-043.
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