textproduct: Fairbanks

SYNOPSIS

Monday, expect another round of scattered thunderstorm in the southern half of the Interior. A Red Flag Warning for convection is out for areas around McGrath to Fairbanks to Eagle and south. Tuesday and Wednesday, a cold front will advance from the southeast bringing in stratiform precipitation and pushing thunderstorm chances into the Western Interior. Locally heavy rain and cooler temperatures are expected in the Southeast and Central Interior along with the front with the highest rainfall amounts expected in the Alaska Range which may cause rapid rises of small rivers.

KEY WEATHER MESSAGES

Central and Eastern Interior...

- Warm temperatures continue through Tuesday, with widespread highs in the mid 70s to low 80s. The warmest temperatures continue to be across the Yukon Flats where temperatures around 80F continue Monday with warmer temps up to 85F on Tuesday.

- Scattered afternoon thunderstorms are expected across the Southern Interior Monday with isolated thunderstorms possible over the eastern Brooks Range Monday evening. Thunderstorm coverage lessens and moves northwest through Wednesday.

- A front tracking from east to west brings high rain chances from the White Mountains southward late Monday night through Tuesday night with locally heavy rain and gusty winds possible, especially near the Alaska Range.

- As the front passes through on Tuesday evening, southerly winds across the Alaska Range will briefly swell, with gusts up to 45 mph through Isabel Pass and up to around 35 mph through Windy Pass.

West Coast and Western Interior...

- Temperatures remain seasonably cool along the West Coast, with temperatures in the 50s to 60s. In the Western Interior, highs in the mid to upper 70s are expected to continue through the latter half of the week.

- Scattered thunderstorms are expected in the Upper Kuskokwim Valley Monday afternoon, with isolated thunderstorms in the Middle and Lower Yukon Valley. Thunderstorm coverage becomes more isolated but continues to be highest in the Southeast Interior.

North Slope and Brooks Range...

- A frontal boundary brings rain chances to the central Arctic Coast and widespread clouds Monday morning before clearing by Tuesday morning.

- Temperatures along the North Slope and in the Northern Brooks Range valleys will see highs in the 60s or low 70s today, with temperatures warming into the upper 60s or low 70s Tuesday and Wednesday. Temperatures begin a cooling trend on Thursday. - There is a slight chance for isolated thunderstorms will over the Eastern Brooks Range today and Tuesday before thunderstorm chances increase on Wednesday.

FORECAST ANALYSIS AND DISCUSSION

The upper-level pattern this morning consists of ridging over the mainland of Alaska with an Arctic trough to the north of us and a 551 decameter low in the Gulf. The Arctic trough will be relatively low impact, bringing winds gusting up to 25 mph across the northern Arctic Coast today, as well as a chances for light rain from Utqiagvik in the morning to Deadhorse in the afternoon. The more influential feature is the low in the Gulf. On Monday it will support another round of scattered thunderstorms in the southern Interior, although isolated thunderstorms will be possible in the eastern Brooks Range as well. The area for Thunderstorm coverage today extends from the Lower Yukon and middle Kuskokwim Valley to the White Mountains and Fortymile Country. Thunderstorms in the White Mountain/Fortymile region appear more stationary as they develop over the higher terrain while storms in the southwest region should track east to west through the afternoon, potentially increasing storm longevity and the area lightning could reach. Beyond the thunderstorms, Monday will be another warm, sunny day for most of Northern Alaska.

Tuesday, the low in the Gulf sends a front into the southeast Interior. This front will bring good chances for widespread rain along with it, as it travels north into the Eastern Interior. In addition to the rain, southerly winds through the Alaska range will be gusty, up to around 40 to 45 mph, with the peak looking to be sometime Tuesday afternoon. Precipitation becomes stratiform behind the front, and areas of heavy rain may develop with totals greater than 0.50" in the Alaska Range. Isolated thunderstorms may still develop in areas ahead of the front as the ridge is broken down. As a result the area for potential thunder becomes angled from the Southwest Interior to the northeast. Behind the front temperatures will be cooler and winds will be gusty and southerly. Areas outside of the Central and Eastern Interior will be largely unaffected by this system resulting in warm and dry weather in the Western and North Slope regions.

Wednesday, the front begins to stall, oriented southwest to northeast over the middle of the state. The high pressure on the western side of the front will support more warm and dry conditions for the Western Interior and North Slope, as well as afternoon thunderstorms from the Lower Yukon to the Eastern Brooks Range. Meanwhile the rest of the Interior will get cooler and cloudier conditions

FIRE WEATHER

Following yet another active thunderstorm day across the Interior yesterday with over 6000 CG lightning strikes in Alaska and the Yukon, another round of isolated to scattered showers and thunderstorms are expected to develop around midday and continue through this evening. The primary convection corridor will extend from the Alcan Border west to Fairbanks and southwest to the Y-K Delta. Scattered thunderstorms are most likely from Fortymile Country to McGrath, where another Red Flag Warning has been issued from 1000 to 2200 AKDT. Stronger storms will continue to be capable of producing frequent lightning, brief heavy rain, and wind gusts up to 30 mph. Winds are expected to remain light outside of any convection, with widespread highs in the 70s and 80s south of the Brooks Range and locally cooler conditions along the coast.

By Monday night into Tuesday morning, rain showers and embedded thunderstorms associated with a frontal system are expected to begin across the Southeast Interior and spread west across the Southern Interior. This frontal system is expected to bring steadier rainfall rates and a swath of wetting rains across the Southern Interior. As the front passes, cloud cover and rainfall will work to limit high temperatures and raise RH values, leading to cooler temperatures where the bulk of precipitation is falling. This front is expected to stall roughly between McGrath and Bettles by Wednesday into Thursday. Widespread wetting rains are expected across the Southern Interior and Alaska Range during this timeframe with preliminary totals around 0.10-0.50", locally higher in the Alaska Range closer to 0.50-1.50". Precipitation totals elsewhere just outside of this Southern Interior region will see totals closer to a T-0.10". Widespread cloud building in out of the southeast Tuesday will push thunderstorm coverage farther north across the Interior towards the eastern Seward Peninsula and Y-K Delta. Thunderstorms will shift even more so come north and west on Wednesday, with more limited isolated thunderstorm potential across much of the Interior outside of a corridor from the Southwest Interior to NE Brooks Range.

Looking ahead, that front in the Central Interior south to Southcentral Alaska looks to begin to weaken later in the day Wednesday into Thursday. While steadier precipitation chances will begin to subside, increased sunshine will lead to an increase in areal coverage of thunderstorms starting Thursday with the return of isolated to scattered coverage back through the weekend across much of the Interior north to the Brooks Range and southwest to the Y-K Delta. Temperatures, while holding steady at near to above normal levels through midweek, will begin to slowly cool by the weekend as broad upper level ridging over much of our region is replaced by troughing building in out of the west.

HYDROLOGY

A front will move westward through the state this week. As this front progresses, it will produce widespread rain showers and isolated thunderstorms. Showers and thunderstorms are expected to begin Tuesday morning in the eastern Alaska Range and upper Tanana Valley and spread northwest through Tuesday night. The heaviest rainfall is expected to fall throughout the day Tuesday. Widespread rainfall totals of 0.5" to 1" and locally higher amounts >2" possible will combine with glacial runoff to result in rising mainstream river levels around the Alaska Range for the middle to end of this week. Rapid rises of smaller rivers are possible with the heaviest rain on Tuesday into Wednesday.

By Wednesday, this front will be set up over the Western Interior and become relatively stationary, allowing for more precipitation to fall through Thursday afternoon. Upwards of 1" or more is expected in the Upper Kuskokwim area near McGrath and Lake Minchumina for this event.

EXTENDED FORECAST DAYS 4-7

For Thursday through Sunday. At the start of the extended period, the upper level low in the Gulf of Alaska progressively moves farther east towards the Alaskan Panhandle. As it does so, it will continue to support isolated to scattered showers and thunderstorms across a corridor extending from Southwest Alaska towards the Eastern Brooks Range. Anomalously high precipitation amounts are expected for the YK Delta and Alaska Range through Thursday. A series of shortwaves moving from east to west off of the Gulf low will continue to support isolated showers and thunderstorms across the Central/Eastern Interior, but will mainly be confined to the higher terrain. A new pattern starts to take hold on Friday as an upper level low moves up the Aleutian Chain and into the Bering Sea. Where this low ends up is a bit uncertain right now, but model guidance is hinting at this low tracking east into Bristol Bay by Sunday morning. This new system is expected to bring widespread cooler temperatures in the 60s and continued showers to the much of the region through the weekend.

Coastal Hazard Potential Days 3 and 4...None

AFG WATCHES/WARNINGS/ADVISORIES

AK...Red Flag Warning for AKZ935>945-947-951>953. PK...None.