textproduct: Fairbanks

KEY MESSAGES

Central and Eastern Interior... - Temperatures are expected cool slightly Friday and Saturday and bottom out Sunday in the upper 50s to mid 60s.

- A frontal system will bring as high as 0.2 to 0.5 inches of precipitation from Bettles to Minchumina Friday into Saturday, with lesser amounts to the East. Another low entering the southwest Yukon increases chances of wetting rains slightly in the Upper Tanana Valley.

- Chances of thunderstorms are likely Friday and Saturday afternoon with the greatest probability of thunderstorms Friday, localized to the Central Eastern Interior. Thunderstorms Saturday afternoon are expected to remain more isolated towards the Northern Eastern Interior.

West Coast and Western Interior... - A cold front will move across the West Coast Friday, and bring with it gusty winds, locally higher tides (no flooding is expected), and another round of moderate to heavy rainfall. - Widespread rain totals over 0.5 with Norton Sound and foothills of the Brooks Range having the possibility to receive up to 1.5 inches.

- Northerly wind gusts through the Bering Strait increase Friday evening with gusts up to 35 mph possible. Winds diminish Saturday morning.

- Temperatures cool slightly following the front. Highs in the 50s to near 60 expected Friday through the weekend and into early next week.

North Slope and Brooks Range... - A brief period of mixed precipitation is possible near Prudhoe Bay and Kaktovik overnight Saturday into Sunday morning. However chances of accumulation remain low at this time.

- A front sweeps across North Slope Friday and Saturday. It brings the potential for traces of snow, with 1-3 inches possible in the Northeastern Brooks Range.

- Expect highs in the upper 30s/low 40s after the front passes through, which will be Saturday west of Umiat and Sunday from Umiat east.

SYNOPSIS

A low pressure system will move across Alaska bringing with it wet and cooler conditions throughout the upcoming weekend. As a cold front continues to approach today from the Bering Sea, it will bring with it wetting rains along the West Coast, gusty winds, and cooler temperatures following the front. As the front shifts northeastward, mixed precipitation will be possible Saturday night into Sunday morning over the Northeast Arctic Coast. Isolated thunderstorms are expected to continue for the Eastern Interior today and tomorrow.

SHORT TERM /THROUGH SUNDAY NIGHT/

Broad troughing is dominating our weather pattern over Northern Alaska. The main parent low is stationed in the high Arctic north of Siberia allowing for west-southwest flow over the area. Southeast of this low is a potent area of energy over the Bering Strait and Eastern Bering Sea. Over the Gulf, there is a weak closed upper low. The energy over the Bering is bringing clouds and wet weather to Western Alaska through Saturday. On the North Slope, southwesterly flow aloft will result in subtle downsloping, keeping it mostly dry and warm to the east, with cool and wet weather west. In the Central and Eastern Interior, southwesterly flow will lead to clouds and areas of showers. This afternoon as the pattern continues to progress eastward, weak lobes of vorticity will meander from south to north over the C/E Interior and during peak heating, there will be enough instability to force isolated thunderstorms. Moving into Saturday, the parent low remains nearly stationary but the energy over the Bering will dig significantly to the south and make a b-line towards the Gulf. As this digs, it will force the low in the Gulf northeast towards The Yukon. Previously it looked like this would bring substantial rain to the Eastern Interior but now, it looks like the bulk of the steadiest rain stays east of the AlCan Border. Regardless, there will be showers over the C/E Interior on Saturday. Steady rain out west will persist but be diminishing in coverage as the energy drops south. On the North Slope, showers will continue as well.

Moving into the latter half of the weekend, the parent low in the Arctic will still be in nearly the same location. This will allow another potent piece of energy to move towards Western Alaska. This one however, will come with a surface low which may end up being around 980-990mb as it tracks into the Northern Bering. This low would bring another dousing of rain, strong wind and the potential for high water which will be elaborated on in the Coastal Hazard Potential section.

Otherwise, something else we'll be monitoring is snow on the North Slope and in the Brooks Range. A weak cold front will briefly dip into the North Slope Sunday afternoon and night. This colder air will help change rain over to snow on Sunday. In Kaktovik, the rain may briefly switch to a period of freezing rain or sleet before the snow Sunday afternoon but this won't be enough to result in any ice accretion. Any snow accumulations after this changeover would be minor as well. In the Brooks Range, there may be minor snow accumulations, especially in Atigun Pass, but most spots will see less than 1 inch of accumulation.

LONG TERM /MONDAY THROUGH WEDNESDAY/

There is quite a bit of uncertainty heading into the long range as there are many moving parts. The overall trend is looking like troughing persists over Northern Alaska with a series of fronts and/or low pressures systems moving towards the West Coast every 1 to 2 days. The main culprit for this is the low in the Arctic and Pacific high moving northward towards the Aleutians, allowing for a storm track through the Bering. As these fronts continue to move through, there will be rain chances across most of Northern Alaska, strong wind on the West Coast and periods of higher than normal water levels. Coastal flooding is not a major concern at this time due to the relatively weak nature of the lows, but with continued heavy rain, rivers may not have sufficient time to drain completely before the next dousing of rain. The bust potential with this forecast is high though, as the pacific high could be a little weaker allowing for the storm track to shift south, or stronger, allowing for a farther north storm track. There is also a very active Pacific jet stream into the Bering which could shift north/south. Minor shifts will be the difference between rounds of heavy rain into Northern Alaska or the Aleutians and Gulf Coast. Regardless, it is looking like fall in the Bering with an active pattern ahead.

FIRE WEATHER

No concerns in the Western Interior where it will continuously be wet and cool through next week.

The Interior is a different story but not inherently "bad". Temperatures will be mild, in the mid to upper 60s, warmest in the Upper Tanana Valley through Saturday. Min RHs in most spots will be above 50% but the Upper Tanana Valley will be around 30-40% through Saturday. Southwest winds will be mainly weak across the Interior today but will gradually increase on Saturday around the AK Range. Southerly winds through the AK Range may gust upwards of 40 mph in Isabel Pass and 35 mph in Windy Pass on Saturday. This will also bring some concern to the Upper Tanana Valley where southwest wind gusts may be upwards of 15 to 20 mph Saturday afternoon. Winds weaken through the AK Range on Sunday and we will be noticing a shift in direction to the Northwest. The northwest winds like to get funneled through the Tanana Valley and increase in speed. Sustained winds may increase to 10-15 mph with gusts upwards of 20-30 mph for most of Sunday.

In terms of precipitation, isolated to scattered showers are expected to continue across the Interior today with spotty wetting rains likely to occur. A thunderstorm is possible in the Eastern Interior as well and IF a storm can develop north of Tok, it could bring a gusty outflow boundary from the north. Otherwise, showers continue on Saturday and Sunday. The highest chances for wetting rains will be in the Eastern Interior north of the Upper Tanana. However, any shower will be capable of producing 0.05-0.15" so it is not completely unreasonable to think Tok can get a brief wetting rain from a shower, but it will be difficult for that to come to fruition.

HYDROLOGY

No concerns for rivers at this time. Even with all of the rain expected in the Western Interior, river levels are low and are not expected to rise tremendously through the weekend.

AFG WATCHES/WARNINGS/ADVISORIES

AK...None. MARINE...Small Craft Advisory until 4 PM AKDT this afternoon for PKZ801. Small Craft Advisory from 1 AM to 6 AM AKDT Saturday for PKZ801-802. Small Craft Advisory from 4 AM to 6 AM AKDT Saturday for PKZ805-852. Small Craft Advisory from 4 PM this afternoon to 6 AM AKDT Saturday for PKZ806-807. Gale Warning from 1 AM to 4 AM AKDT Saturday for PKZ806. Small Craft Advisory from 10 PM this evening to 6 AM AKDT Saturday for PKZ810-850-853. Small Craft Advisory from 4 PM this afternoon to 4 AM AKDT Saturday for PKZ816. Small Craft Advisory from 1 PM this afternoon to 6 AM AKDT Saturday for PKZ817-854. Small Craft Advisory from 10 AM this morning to 1 PM AKDT this afternoon for PKZ850. Small Craft Advisory from 10 PM this evening to 1 AM AKDT Saturday for PKZ851. Small Craft Advisory from 7 PM this evening to 6 AM AKDT Saturday for PKZ856.