Severe Thunderstorm Warning 1, NWS Fairbanks, AK

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
229 AM AKDT SUN JUN 22 2008

.DISCUSSION...
MODELS IN DECENT AGREEMENT THROUGH 60 HOURS FOR THE MOST PART.
MODELS HAVE INTRINSIC DIFFERENCES WHICH DO NOT GREATLY AFFECT
OVERALL PATTERN PROGS.

UPPER LEVEL RIDGE ORIENTED IN AN EAST TO WEST AXIS WILL CONTINUE
TO MOVE NORTHWARD OVER THE NORTHERN INTERIOR NEAR THE BROOKS RANGE
BY TONIGHT. THIS IS BEING FORCED NORTHWARD BY A MODERATELY WEAK
LOW IN THE GULF OF ALASKA.

CONVECTIVE PARAMETERS FOR SATURDAY WERE WELL ADVERTISED BY THE
CONVECTIVE INDICES FROM THE NGM AND THE NAM PROGS. AGAIN...THESE 2
MODELS ARE INDICATING ANOTHER POTENTIALLY ACTIVE CONVECTIVE DAY
OVER THE CENTRAL INTERIOR. THE SHOWALTER INDEX SUGGESTS MODERATELY
INSTABILITY FROM ABOUT FAIRBANKS NORTHWARD TO THE BROOKS RANGE.
ALSO WITHIN THIS AREA DELTA T VALUES ARE BETWEEN 30 AND 32.
THE SAME TYPE OF SCENARIO WILL BE EXPERIENCED TODAY...BELIEVE
THERE IS A DECENT POTENTIAL FOR DRY THUNDERSTORMS ONCE AGAIN OVER
THE INTERIOR. THIS DOES NOT BODE WELL UNDER A SUBSIDENCE REGIME WHICH
WILL ENHANCE FIRE POTENTIAL WITH STRIKES.

THE SAME MODELS DIVERGE A BIT FOR MONDAY BUT CONTINUE TO INDICATE
THAT THE MOST ACTIVE CONVECTIVE LOCATIONS WILL BE IN THE NORTHERN
INTERIOR ALONG THE BROOKS RANGE FROM ZONE 217 EASTWARD. THE
CENTRAL INTERIOR WILL BEGIN TO COOL AT LOWER LEVELS WHICH WILL
KNOCK DOWN THE DELTA T VALUES AND CREATE A MORE STABLE AIR MASS
OVER THE AREA.

THE LOW MOVING INTO NORTHERN GULF OF ALASKA WILL SPREAD MOISTURE
INTO THE LOWER LEVELS IN THE CENTRAL INTERIOR. THIS WILL INCREASE
RH VALUES OVER THE EASTERN AND CENTRAL INTERIOR TODAY BUT THE
NORTHERN INTERIOR WILL CONTINUE TO SEE LOWER RH VALUES. AN
EMBEDDED SHORT WAVE IN THE UPPER LEVEL RIDGE WILL SERVE AS AN
ADDITIONAL POTENTIAL TRIGGER FOR CONVECTIVE POTENTIAL TODAY OVER
THE CENTRAL AND EASTERN INTERIOR.

THE WEST COAST WILL SEE THE UPPER LEVEL TROUGH RETURN TO THEM BY
THE FIRST OF THE WEEK WITH COOLER TEMPERATURES MOVING BACK IN AND
THEY WILL REMAIN IN THAT PATTERN THROUGH THE END OF THE WEEK. THE
STORM TRACK WILL REMAIN WELL THE SOUTH OF THE ZONES THEREFORE
LIMITING SIGNIFICANT PRECIPITATION EVENTS.

THE ARCTIC COAST WILL SEE WARMING OVER MOST OF THE AREA THROUGH
ABOUT WEDNESDAY AND IN PARTICULAR THE EASTERN ARCTIC WITH THE
UPPER LEVEL RIDGE MOVING NORTHWARD. IN FACT...IT WOULD NOT BE OUT
OF THE QUESTION TO SEE DECENT CONVECTION DEVELOPMENT ON THE ARCTIC
PLAIN FROM PRUDHOE BAY EASTWARD ON TUESDAY AS CURRENT PROGS SUGGEST.

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...NONE

&&

.FIRE WEATHER...BELIEVE THERE IS DECENT POTENTIAL FOR DRY
THUNDERSTORMS ONCE AGAIN TODAY OVER THE CENTRAL AND NORTHERN INTERIOR.

&&

.HYDROLOGY...NONE.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
BRISK WIND ADVISORY FOR PKZ245.
&&

CF JUN 08