Dust Devil in Alaska, July 12, 2015

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
130 PM AKDT SUN JUL 12 2015

.DISCUSSION...

ALOFT AT 500 MB...THE 547 DAM LOW LOCATED OVER 75N AND 147W WILL
CONTINUE TO MOVE WESTWARD AND DEVELOP A TROUGH EXTENDING SOUTHWARD
TO THE CHUKCHI SEA BY MONDAY NIGHT AND DEVELOPING INTO A 548 DAM
LOW BY WEDNESDAY. MEANWHILE THERE ARE SOME DIFFERENCE IN THE
MODELS WITH THE ECMWF TRYING TO FORM AN UPPER LOW JUST NORTH OF
BARTER ISLAND ALONG THE BEAUFORT COAST WHILE THE GFS KEEPS A
SHORTWAVE ACROSS THE AREA. TIMING SEEMS TO BE THE BIGGEST ISSUE AS
THE GFS DOES DEVELOP A LOW BUT ROUGHLY 12 HOURS LATER. IN EITHER
CASE THIS WILL BRING SOME DRIZZLE OR LIGHT PRECIPITATION TO MARINE
AND OFF SHORES MARINE ZONES ON WEDNESDAY ALONG THE ARCTIC COAST.
FOR THE INTERIOR...THE MAIN IMPACTS WILL BE FROM A COUPLE EASTERLY
WAVES WHICH IS BASICALLY ROTATING ENERGY AROUND A DOUBLE BARREL
LOW THAT DEVELOPS BY MONDAY MORNING WITH ONE LOW SOUTH OF PRIBILOF
ISLANDS AND THE OTHER SOUTH OF KODIAK ISLAND. WE ALREADY HAVE ONE
SHORTWAVE MOVING NORTHWARD ACROSS THE EASTERN INTERIOR TODAY AS
THE WEAK RIDGE GETS PUSHED NORTHWARD. THE STRONGEST EASTERLY WAVE
WILL MOVE ACROSS THE EASTERN AND CENTRAL INTERIOR ON TUESDAY
AFTERNOON INTO THE WESTERN INTERIOR ON WEDNESDAY WHERE WE SHOULD
SEE SOME DECENT PRECIPITATION AMOUNTS AND INCREASED CHANCE OF
WETTING RAIN FOR FIRE SITUATIONS.

AT THE SURFACE...THE THERMAL TROUGH REMAINS ACROSS THE CENTRAL
INTERIOR EXTENDING FROM EAGLE TO GALENA WITH THE SURFACE LOW 0F
998 MB LOCATED OVER THE TANANA BASIN THIS EVENING. THE THERMAL
TROUGH WILL REMAIN NEARLY STATIONARY THROUGH MONDAY AS THE LOW
MOVES 1002MB OVER FORTY MILE COUNTY BY MID MORNING. THE THERMAL
TROUGH WILL THEN MOVE NORTHWARD ON TUESDAY MORNING EXTENDING FROM
A LINE FROM CHALKYITSIK TOWARD HUSLIA AND THEN DEVELOP INTO A 999
MB LOW AROUND BETTLES. MEANWHILE ACROSS THE ARCTIC HIGH PRESSURE
REMAINS OVER THE ARCTIC OCEAN TONIGHT AND THEN SLOWLY DIMINISHES
AS A 1001 MB LOW DEVELOPS OVER THE CHUKOTSK PENINSULA ON MONDAY
AND TUESDAY.

ARCTIC COAST AND BROOKS RANGE...WITH THE HIGH PRESSURE OVER THE
ARCTIC EXPECT ONSHORE FLOW WITH STRATUS AND DENSE FOG
REDEVELOPING OVERNIGHT. HAVE PLACED DENSE FOG HEADLINES FOR AREAS
FROM BARROW EASTWARD ALONG THE BEAUFORT COAST. THERE WILL ALSO BE
AREAS OF DRIZZLE THAT CAN BE EXPECTED AS WELL...WITH BETTER
CHANCES OF SHOWERS AND ISOLATED THUNDERSTORMS OVER THE EASTERN
BROOKS RANGE. BY MONDAY THE WINDS WILL START TO SEE WIND SHIFT
ALONG THE CHUKCHI SEA COAST FROM EASTERLY TO NORTH AND NORTHWEST
AS A TROUGH DEVELOPS. THE BROAD AREA LOW NEAR BETTLES BY WEDNESDAY
MORNING WILL MOVE TO THE NORTHEAST ACROSS THE WESTERN BROOKS RANGE
BRINGING INCREASES PRECIPITATION CHANGES TO THE AREA LATER IN
WEEK.

WESTERN COAST AND WESTERN INTERIOR...MISSING THE SATELLITE VIIRS
IMAGERY...BUT STILL ABLE TO UTILIZE THE 24HR MICROPHYSICS RGB
PRODUCT FROM MODIS IN THE LATE MORNING WHICH HIGHLIGHTS THE
STRATUS CLOUDS THAT MOVED ALONG THE KOTZEBUE AREA. HOWEVER
AFTERNOON SHOWERS HAVE STARTED TO DEVELOP OVER THE YUKON DELTA AND
WILL SHIFT NORTHWARD AND EXPAND IN COVERAGE WITH GREATEST CHANCES
EXTENDING FROM ANVIK TO RUBY. DENSE SMOKE LINGERED ACROSS SMILIER
AREA AROUND RUBY THROUGH NOON TODAY. ALTHOUGH THE SMOKE HAS
FINALLY STARTED TO INCREASE VISIBILITIES TO AROUND 2 MILES IN
MANY LOCATIONS DUE TO MIXING THROUGH THE DAY AND ADDED SHOWERS
WILL HELP...RUBY STILL REMAINS AT HALF MILE AS OF 1 PM. THUS HAVE
EXTENDED THE DENSE SMOKE ADVISORY THROUGH MONDAY MORNING.
INCREASED CHANCES OF PRECIPITATION QUARTER TO HALF AN INCH ON
TUESDAY NIGHT.

CENTRAL AND EASTERN INTERIOR...ISOLATED THUNDERSTORMS ARE ALREADY
POPPING UP THIS AFTERNOON ON THE PEDRO DOME RADAR WITH LIGHTING
STRIKES WITH THE STORM JUST SOUTHEAST OF STEVENS VILLAGE AND SOME
WITH THE STORMS LOCATED BETWEEN MCGRATH AND GALENA. EXPECTED
COVERAGE TO EXPAND FROM ALASKA RANGE TO FAIRBANKS TO FORTY MILE
COUNTRY TONIGHT AND OVERNIGHT. ALREADY STARTING TO SEE OUTFLOW
BOUNDARY DEVELOP JUST NORTHEAST OF FAIRBANKS ON THE RADAR. THE
STORM LOCATED NEAR THE AGGIE WILDFIRE HAD SOME RAIN AND SMALL HAIL
WITH THE STORM CELL. WILL SEE DEVELOPMENT AND COVERAGE INCREASE
ON MONDAY AFTERNOON EXTENDING FROM MCGRATH TO NORTHEAST OF CIRCLE
WITH PRECIPITATION AMOUNTS UP TO A QUARTER INCH WITH HALF AN INCH
WITH THE STRONGER STORMS. HOWEVER...CHANCES INCREASE WITH THE
EASTERLY WAVE MOVING ACROSS THE INTERIOR ON TUESDAY AFTERNOON INTO
WEDNESDAY. THE NAM MODEL SUGGEST HIGHER PRECIPITATION AMOUNTS WITH
UP TO 1 INCH POSSIBLE BUT OTHER MODELS ARE LESS. GIVEN THE
UNCERTAINTY IN THE MODELS...EXPECT GENERAL PRECIPITATION AMOUNTS
OF 0.25 TO 0.75 INCHES...WITHIN AREA FROM LAKE MINCHUMINA TO
CIRCLE.

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...NONE

&&

.FIRE WEATHER...
MOISTURE WILL INCREASE AND SPREAD ACROSS THE INTERIOR TODAY AND
CONTINUE TO INCREASE THROUGH MID NEXT WEEK WITH INCREASED CHANCES
OF PRECIPITATION AND CHANCE OF WETTING RAIN. THE THERMAL TROUGH
NORTH OF THE ALASKA RANGE WILL MOVE SLOWLY MOVE NORTH OVERNIGHT
AND MONDAY. A STRONGER EASTERLY WAVE WILL MOVE ACROSS THE AREA ON
TUESDAY AFTERNOON INTO WEDNESDAY...BRINING DECENT POTENTIAL FOR
WETTING RAINS. ALTHOUGH THERE IS STILL UNCERTAINTY WITHIN THE
MODELS THE INITIAL PRECIPITATION AMOUNTS OF 0.25 TO 0.75 INCHES
EXTENDING ACROSS AN AREA FROM LAKE MINCHUMINA TO CIRCLE WITH
POTENTIAL FOR HIGHER POCKET AMOUNTS WITH STRONGER STORMS MAY BE
POSSIBLE.

&&

.HYDROLOGY...
DO NOT EXPECT ANY RISE IN THE RIVERS FOR THIS AFTERNOON.
HOWEVER MAY SEE A SLIGHT RISE IN THE CREEKS ESPECIALLY WITH THE
EASTERLY WAVE EXPECTED ON TUESDAY NIGHT INTO WEDNESDAY. ALTHOUGH
STILL SOME UNCERTAINTY WITHIN THE MODELS GENERALLY EXPECTING
PRECIPITATION AMOUNTS OF 0.25 TO 0.75 INCHES WITH SOME LOCALLY
HEAVIER POCKETS WITH STRONGER THUNDERSTORMS. THE MODELS WERE
HINTING THAT THIS WOULD FALL IN THE UPPER PORTIONS KUSKOKWIM RIVER
BASINS AS WELL AS THE CHATANIKA...CHENA..AND SALCHA RIVER BASINS.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
DENSE SMOKE ADVISORY FOR AKZ216-AKZ221-AKZ227.
&&

MAK JUL 15