Brisk Wind Advisory 166, NWS Fairbanks, AK

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
503 AM AKDT THU JUN 4 2009

.DISCUSSION...THE NAM AND GFS MODEL FORECASTS ARE SIMILAR THROUGH
FRIDAY NIGHT. BOTH FORECAST MODERATE HIGH PRESSURE OVER THE
NORTHEAST BEAUFORT SEA TO RETREAT NORTHWARD. ALTHOUGH WINDS ON THE
ARCTIC COAST ARE RATHER LIGHT NOW, THERE IS BRISK EASTERLY FLOW
OFFSHORE. THIS IS A COMMON PATTERN WITH STRONG HIGH PRESSURE OVER
THE NORTHEAST BEAUFORT SEA.

A THERMAL TROUGH OF LOW PRESSURE WILL HOLD OVER THE BROOKS RANGE
AND THE SOUTHEAST INTERIOR AND WEAKEN TONIGHT. THIS FEATURE IS
EXPECTED TO AGAIN BY THE FOCUS FOR CONVECTION, AND SOME ISOLATED
THUNDERSTORMS ARE EXPECTED INLAND OVER THE EASTERN ARCTIC THIS
EVENING. THE ALASKA LIGHTNING DETECTION SYSTEM PICKED UP 45
STRIKES, NEARLY ALL OF THEM ALONG THE MIDDLE COLVILLE RIVER, ON
WEDNESDAY. THUS, TODAYS FORECAST CALLS FOR A VERY SIMILAR AREA
FOR THUNDERSTORMS, SHIFTED A LITTLE TO THE EAST FROM WEDNESDAY.

THE ONLY IMPORTANT INCOMING SYSTEM IS A MODERATE 992 MILLIBAR LOW
PRESSURE SYSTEM TO MOVE NORTH ACROSS THE ALASKA PENINSULA INTO THE
SOUTHEAST BERING SEA THIS AFTERNOON, AND NORTHWESTWARD OVER THE
PRIBILOFS TONIGHT. MOST OF THE INCOMING ENERGY WITH THIS SYSTEM
WILL BE FOCUSED OVER THE ALASKA PENINSULA AND BRISTOL BAY. A
BRIEF NORTHEAST GALE IN ADVANCE OF THIS LOW IS EXPECTED FROM DALL
POINT TO BERING STRAIT THIS EVENING.

THE CIRCULATION ALOFT THIS MORNING IS SOUTHWESTERLY, AROUND A
LARGE HIGH ALOFT OVER THE QUEEN CHARLOTTE ISLANDS OFF BRITISH
COLUMBIA. A WEAK SHORT WAVE IN THIS CIRCULATION WILL MOVE UP OVER
THE BROOKS RANGE THIS AFTERNOON AND OFFSHORE THE ARCTIC COAST THIS
EVENING. THIS SHORT WAVE IS EXPECTED TO GIVE SOME SUPPORT TO THE
THUNDERSTORMS EXPECTED THIS EVENING OVER THE EAST ARCTIC INTERIOR.

MODERATE LOW PRESSURE ALOFT WILL MOVE INTO THE SOUTHEAST BERING
SEA THIS EVENING AND TO SAINT MATTHEW ISLAND TONIGHT. CIRCULATION
OVER THE REALM WILL BECOME SOUTHERLY AND INCREASE IN STRENGTH
TONIGHT THROUGH FRIDAY NIGHT. A MODERATE TROUGH ALOFT WILL MOVE
NORTHWARD OVER THE ALASKA MAINLAND FRIDAY NIGHT AND SATURDAY.
TEMPERATURES ALOFT OVER THE EAST INTERIOR WILL COOL SUBSTANTIALLY
AND THERE WILL BE SOME RAIN AS THIS SHORT WAVE MOVES THROUGH.

HIGH TEMPERATURES IN THE EASTERN INTERIOR ARE EXPECTED TO BE IN
THE 80S TODAY, BUT 90 DEGREE READINGS APPEAR JUST OUT OF REACH.
BY SATURDAY, HIGHS WILL NOT REACH BEYOND THE 70S.

MOST OF THE PRECIPITATION OVER NORTHERN ALASKA DURING THE NEXT 48
HOURS WILL BE OVER THE BERING SEA COAST. A WEAK TROUGH ALOFT WILL
MOVE UP OVER THE WESTERN MAINLAND SATURDAY NIGHT AND SUNDAY. THIS
MAY BRING SOME SHOWERS TO THE WEST AND CENTRAL INTERIOR.

ON SUNDAY, THE HIGH ALOFT WILL BEGIN TO REBUILD FROM THE SOUTHERN
YUKON INTO THE ALASKA INTERIOR. THIS WILL PROBABLY BRING AFTERNOON
HIGH TEMPERATURES INTO THE 80S AGAIN ON MONDAY.

THE GFS AND EUROPEAN MODEL FORECASTS ARE SIMILAR THROUGH SUNDAY.
BEYOND THEN, THE WEAK CIRCULATION ALOFT FORECAST BY THE GFS LOOKS
A MORE REALISTIC THAN THE WELL DEFINED SOUTHERLY CIRCULATION OF
THE EUROPEAN MODEL FORECAST. BY EARLY NEXT WEEK, WEAK CIRCULATION
ALOFT OVER THE MAINLAND, MOST OF IT WITHIN WEAK HIGH PRESSURE,
WILL FAVOR SUNNY WEATHER, ABOVE NORMAL TEMPERATURES AND SOME LATE
AFTERNOON AND EVENING THUNDERSTORMS OVER THE INTERIOR, CLOUDY
SKIES AND SOME LIGHT RAIN IN THE WEST, AND COOL, CLOUDY WEATHER
OVER THE ARCTIC COAST. IN 3 WORDS: TYPICAL EARLY SUMMER.

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...NONE.

&&

.FIRE WEATHER...LOW HUMIDITY AND HIGH TEMPERATURES IN THE 80S IN
THE EASTERN INTERIOR IN THE LATE AFTERNOON/EARLY EVENING TODAY.
THE LATE AFTERNOON/EARLY EVENING HUMIDITY ON FRIDAY WILL NOT BE AS
LOW WITH THE INFLUX OF SOME MOISTURE AND MID AND HIGH LEVELS.
THERE WILL BE A REAL RISE IN HUMIDITY ON SATURDAY DUE TO COOLING
AFTERNOON TEMPERATURES.

&&

.HYDROLOGY...BREAKUP IS OVER AND THE INCOMING PRECIPITATION IN THE
WEST WILL BE VERY LIGHT FOR THE REST OF THIS WEEK. THUS, RIVER
LEVELS WILL CONTINUE TO GRADUALLY DROP.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY FOR PKZ210-PKZ210.

GALE WARNING FOR PKZ210.

BRISK WIND ADVISORY FOR PKZ200-PKZ240-PKZ245.
&&

TF JUN 09