Area Forecast Discussion

SYNOPSIS

Key Messages:

- Drier weather and warmer temperatures for Friday.

- A front arriving on Saturday brings periods of rain and wind, especially to the northern and central panhandle.

- Periods of moderate to heavy rain expected for Sunday and Monday as a strong system pushes through.

SHORT TERM

Quiet weather is returning to the panhandle through the end of the week, ahead of a strong system which will bring widespread rain and wind for the weekend.

Satellite imagery as of the time of writing shows clearing skies across most of the panhandle this Thursday afternoon, as a ridge begins to build over the area. While pockets of clouds remain, a more northerly component to the winds has resulted in better offshore flow. While the cloud deck could partially rebuild Thursday night, anticipate it to retreat back offshore on Friday. The one noteworthy exception to the improving trend has been Yakutat, where a decaying backdoor trough is bringing periods of rain. This is not a permanent state of affairs, and rainfall will eventually diminish overnight. By Friday morning, drier weather should be in store for the northern gulf as well. Some patchy fog could develop late tonight for Yakutat, as well as for the southern panhandle (for areas south of Frederick Sound), but any fog that forms will swiftly dissipate Friday morning under the mid- June sun.

Saturday will be a tale of two weather regimes, as drier weather early Saturday morning gives way to rain and windy conditions. An advancing warm front will overrun the NE Gulf Coast early in the morning. Expect rain could also impact the outer coast from Cape Ommaney northwards, although the front will rapidly weaken as it tries to push inland, and think that much of the south/central panhandle will see little to no rain from this initial push. A significantly stronger plume of moisture will take aim Saturday night into Sunday at the northern Gulf Coast (specifically Yakutat), before moving E through the day and into Monday across the rest of the panhandle. The exact placement of the plume of moisture initially will depend on the strength of a low developing along it, and how far west said low veers as it arrives in the northern Gulf. Upwards of 2-4 inches of rain are likely to fall for Yakutat proper over 48 hours, with 1-2 inches of rain for the northern and central panhandle, and up to 1 inch for the south. While rainfall amounts are impressive for the dry season, they remain relatively lackluster when compared to stronger fall systems, and most locations are unlikely to break even 1 year Atmospheric Return Intervals (ARIs). For additional information, see the long term forecast discussion.

Temperatures will remain heavily independent on cloud cover, with areas where the cloud deck breaks likely to see high temperatures in the 60s, or even 70s, on Friday. Conversely, the 50s or low 60s remain likely for any location where the cloud deck manages to linger.

LONG TERM.../Sunday through Tuesday/

Sunday looks to be the wettest day across the panhandle due to the front sweeping across the area. Rain will continue in the northern and central part of the panhandle, and based on the speed of the front from current model runs, the southern panhandle is expected to see rain by Sunday afternoon. The heaviest rain the Yakutat area could see is expected overnight Saturday into late morning Sunday, still with a 90% confidence that no more than 1.5 inches will fall in a 6 hour period during this time. Moderate rain is expected on Sunday in the northern and central panhandle, with light rain in the southern panhandle once it starts. With the front passing through Sunday, most locations across the panhandle could see shifting winds with speeds between 10-15 mph. Yakutat could see higher winds, up to 20 mph with strong gusts winds get funneled along the coast line.

The upper level jet aimed at the panhandle through the day Sunday looks to continue to fall south by Monday morning. This will bring calmer onshore flow later in the day Monday that is likely to cause consistent rain to turn to a showery pattern across the panhandle. A very flat upper level ridge looks to take place over the panhandle Tuesday morning, causing some drops in precipitation chances across the area, however the possibility of rain remains present.

Models are picking up on an upper level low that looks to move across the panhandle at the end of next week. This is likely to bring drier and warmer conditions with the offshore flow associated with this pattern.

AVIATION

Conditions across the region continue to improve to VFR Thursday afternoon, with the exception of PAYA which has remained IFR. Anticipate sea breezes to continue this afternoon with winds diminishing late tonight. As winds decrease, anticipate a MVFR marine layer to begin to dominate the coast, trying to push east into the Panhandle. Expect localized areas of IFR along the coast including PAYA, PAGS, and PAKW. Portions of the central Panhandle will also likely see some IFR CIGS or BCFG in Friday morning. Friday conditions improve to VFR after 18z, with sea breezes impacting the region.

MARINE

Outside (Gulf and Coastal Waters): A ridge of high pressure will continue to build over the central and eastern Gulf Thursday night. This will keep winds and seas relatively on the light side with strongest NWLY winds of 15 kt along the outer coast on the lee side of the ridge axis tonight. On Friday, the ridge will shift eastward over the inner channels causing light winds to back around to the S-SE as a low pressure system and associated from moves into the western gulf. Winds with that front will increase over the northern outside waters to 30kt near the typical barrier jet near Cape St. Elias early Saturday and seas building to around 12 feet. Another stronger low pressure system will develop and track northward along the front through Saturday night, causing wind speeds, again in the barrier jet area, to increase to gale force 35-45kt and seas building 14-17 feet going into Sunday. The second front will slowly shift eastward on Sunday with winds over the gulf trending down.

Inside (Inner Channels): Afternoon sea breezes of 10-15kt will continue to dominate winds on the inside today and Friday with lighter drainage winds during the overnight hours. The central and southern inner channels should see wind directions turn our of the NW as the ridge of high pressure sits just offshore through Friday, then slowly back out of the south late Friday as the ridge axis shifts eastward. Once the ridge has passed and the larger frontal system is over the gulf through the weekend, prevailing winds through the inner channels should be influenced by the synoptic flow and remain southerly. Wind speeds have been increased through the inner channels on Sunday when the front is expected to move through. There is potential that wind gusts could be stronger with that front as well.

AJK WATCHES / WARNINGS / ADVISORIES

PUBLIC...None. MARINE...Gale Warning for PKZ652-663-664-671-672. Small Craft Advisory for PKZ053-642>644-651-661-662.