textproduct: Fairbanks

SYNOPSIS

A weakening Bering Sea low is expected to move into the northern gulf, transitioning southerly flow to southeasterly by mid week. Showers and isolated thunderstorms continue through the week, increase in coverage through Thursday, across interior Alaska. There is increasing confidence for warmer temperatures by early to mid next week.

KEY WEATHER MESSAGES

Central and Eastern Interior... - Isolated thunderstorms and scattered showers are expected to continue across most of the Interior throughout the week. The greatest chances for thunder will be in the higher terrain of the Eastern Interior through Wednesday afternoon, with coverage expanding to most of the interior by Thursday.

- Southerly gap winds for the Alaska Range passes will continue into Wednesday, with gusts up to 50 mph are possible. Red flag conditions are expected near Delta Junction this afternoon.

- Consistent temperatures in the low to mid 60s are expected to persist into the weekend, increasing into next week.

West Coast and Western Interior... - Scattered showers and isolated afternoon thunderstorms continue across the Western Interior and parts of the Seward Peninsula this week. Showers and thunderstorm chances gradually decrease and become more isolated going into the weekend.

- Gusty northeast winds continue across the West Coast today, paricularly near the Bering Strait. Winds are expected to decrease through mid week then remain mostly steady until the weekend.

- Consistent temperatures in the upper 50s to low 60s will persist until steadily increasing early next week.

- Patchy dense fog is possible across the West Coast each morning this week.

North Slope and Brooks Range... - Slightly cooler than normal temperatures continue across the North Slope with highs in the mid to upper 20s and lows in the upper teens. Temperatures have a high likelihood of exceeding freezing for a high, ranging between mid 30s to low 40s.

- East/northeast winds are expected to weaken through tonight, transitioning to offshore winds by the late weekend.

- Low clouds and patchy fog continue across the North Slope through most of the week. Gaps in the clouds become more common further west.

FORECAST ANALYSIS AND DISCUSSION

Broad scale troughing continues over the state as a Bering Sea vertically stacked low near Bristol Bay continues to fill. The jet stream aloft has moved from the southerly flow up into the Alaska Range towards the Coast Mountains near Yakutat and into Canada. Therefore, pressure gradients have begun to relax around the Alaska Range; although are expected to remain elevated through Wednesday morning for Isabel Pass. Furthermore, southerly flow into Delta Junction along with downsloping winds and a lack of recovery overnight has resulted in red flag conditions now expected through 6 PM Tuesday. The lingering front ejected off the Bering Sea low is currently near the Brooks Range, supporting isolated showers and thunderstorms across the Western Interior and higher terrain of the Central/Eastern Interior. Highest rain chances are along the Brooks Range just north of the Yukon Flats, with microwave satellite imagery indicating anywhere between 0.02-0.05 in/hr currently occurring in the aforementioned areas. Wetting rain chances decrease with these storms through Wednesday as PWAT values drop to around 0.30 inches and RH values drop into the 20 to 30% range across much of the region.

Going into Wednesday night, not many changes to the overall forecast package. As the Bering Sea low moves east, it begins to pull a large swath of moisture and shortwave energy south towards the Alaska Range. This will work to increase precipitation and thunderstorm chances over the Central/Eastern Interior Thursday and Friday. Additionally, winds across Interior Alaska will gradually decrease Wednesday through the weekend with winds from the Lisburne Peninsula south towards the Bering Strait remaining gusty at times. Temperatures are expected the hold steady across the state through the rest of the week with models hinting at a slight warm up sometime early next week.

FIRE WEATHER

As a low pressure system tracks from the Eastern Bering Sea into the Gulf of Alaska, winds will weaken across much of the Interior throughout the week as areas of high pressure remain in place over Siberia and Eastern Canada. Strongest winds are expected Tuesday night through the Eastern Alaska Range into Delta Junction where a red flag warning remains in effect until 6 PM AKDT Tuesday night. Gusts up to 50 mph remain possible overnight before weakening throughout Wednesday. The weaker wind pattern combined with increased solar heating will support a gradual warming and drying trend across most of the region. Afternoon minimum RH values will generally fall into the 20s and 30s percent range with poor overnight recoveries on south-facing slopes and higher terrain. Interior temperatures will warm into the mid 50s to 60s through late week with temperatures along the West Coast expected to remain cooler in the mid 50s.

Scattered showers and isolated thunderstorms will continue to develop during the afternoon and evening hours, mainly over areas of higher terrain in the Central and Eastern Interior. Any thunderstorm development will be capable of producing gusty, erratic outflow winds. Wetting rain potential remains limited with many location receiving light and isolated showers.

HYDROLOGY

Yukon River: At 10pm AKDT Monday, the River Watch Team observed the breakup front moving downstream past Emmonak and Alakanuk with a 30 mile run of thick bank to bank ice and high water upstream. There are reports that Kwig Pass is jamming up at the mouth, with water backing up near Emmonak. The high water has caused flooding in upstream areas in conjunction with this ice run. Residents should take precautions now and continue to monitor the situation closely.

A Flood Warning remains in effect for St. Mary's, Emmonak, and Alakanuk. A Flood Watch remains in effect for the Yukon Delta.

Emmonak: As of 745pm Monday, local observers report water is rising steadily with ice only moving in the middle channel. As of 1230pm Tuesday, water has begun to flow over roads near the channel. Local officials advise that the Emmonak High School is a safe place if residents should need to relocate.

Alakanuk: As of 4pm Monday, River Watch observed a run of 20 to 30 miles of heavy ice and high water moving towards the village. Local observers reported minor flooding is occuring, primarily on the south river bank. If ice stops completely, water will rise faster. There was a partial jam noted at the South Mouth with Casey Channel and the Alakanuk Slough as the primary outlets for ice to pass.

Nunam Iqua: As of 2pm Monday, River Watch observed a partial jam near the South Mouth. Ice was primarily flowing through the Casey Channel. Another 20 to 30 miles of heavy ice and high water is expected to make water levels rise through this morning. Residents should take precautions and monitor.

Additional Information: Visit www.weather.gov/aprfc for the latest hydro information.

Please report observed flooding to local emergency services, law enforcement, or to the National Weather Service when you can do so safely.

EXTENDED FORECAST DAYS 4-7

The long term forecast can be broken up into Friday/Saturday, and Sunday into next week. Friday and Saturday see a continuation of the upper level low near the northern gulf with broad troughing across the state. While some uncertainty exists regarding the speed at which the low will move out, better concensus that the upper level low will dig south, bringing in ridging in both western Canada and near Siberia. Therefore, a warmer and drier pattern is in store, with temperatures in the interior ranging from the upper 60s to mid 70s for a high, with around a 50-60% likelihood of exceeding 70 degrees by June 1st.

Coastal Hazard Potential Days 3 and 4...None

AFG WATCHES/WARNINGS/ADVISORIES

AK...Wind Advisory for AKZ849. Wind Advisory for AKZ837. Flood Watch for AKZ825. PK...Small Craft Advisory for PKZ806-811-812-817-850-854-857-858. Brisk Wind Advisory for PKZ807-810-816. Brisk Wind Advisory for PKZ814-815. Brisk Wind Advisory for PKZ851. Small Craft Advisory for PKZ853. Gale Warning for PKZ856. Brisk Wind Advisory for PKZ860-861.