Brisk Wind Advisory 10, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
1145 AM AST MON JAN 16 2006

.DISCUSSION...
IT IS VERY USEFUL TO SEE THE NORTHERN HEMISPHERIC PATTERN AT 500 MB
THIS MORNING. THERE IS MUCH LESS ZONAL FLOW THAN LAST MONTH WITH A
VERY UNBALANCED PATTERN. THE ANCHOR IS OVER GREENLAND WITH A SEVEN
WAVE PATTERN. MAJORS INCLUDE THE LOW SSE OF COLD BAY AND ANOTHER SW
OF SHEMYA AND THE U.S. WEST COAST RIDGE LOOKS PROGRESSIVE. A SHORT
WESTERLY JET IS OFF SOUTHERN JAPAN AND ANOTHER SW BRANCH EXITS OFF
VANCOUVER ISLAND. SATELLITE PIX SHOW 3 GULF LOWS AT 12Z MON WITH THE
MAIN ONE 972 MB NEAR 48N 155W WITH A 976 NEAR 48N 138W SUPPORTED BY
THE JET. THERE IS A NICE COMMA CLOUD S OF KODIAK ISLAND ASSOCIATED
WITH A SECONDARY SURFACE LOW AND A VORTICITY MAX ALOFT. THE OLD
OCCLUDED FRONT IS STALLED IN THE NORTHERN GULF AND RADARS SHOW
SHOWERS SKIRTING ALONG THE COAST MOVING TOWARD THE WEST AND KODIAK.

FORECASTS LARGE SCALE - ALL MODELS AGREE THAT THE WEST COAST RIDGE IS
PROGRESSIVE. THIS SETS UP ANOTHER EVENT OF ZONAL FLOW FROM SOUTHERN
ASIA ONTO THE WEST U.S. COAST ON WED FOR A QUICK CHANGE THIS WILL
ALSO DIRECT WESTERLIES ALOFT OVER MOST OF OUR GIGANTIC FORECAST AREA.

AER FORECASTS - ALL MODELS FORECAST A NEG TILTED UPPER RIDGE OVER THE
CENTRAL BERING SEA ALL DAY WED WITH SOME SORT OF UPPER HIGH OVER PANC
TONIGHT THRU WED. THIS SETS UP A WEAK SURFACE LOW APPROXIMATELY OVER
THE BARREN ISLANDS 00Z THU AROUND 1000 MB OR SO. THE KEY WILL BE THE
SHORT WAVE ALOFT MOVING OVER THE AREA FORM THE SW AT 00Z THU WHICH
MAKES OUR PRESENT SNOW LIKELY FORECAST LOOK OK. FOR THE 12Z AK-ETA-12
OUTPUT THE QPF AMOUNTS INTO THU AND FRI ARE LOW BUT IT IS NOT
UNREASONABLE TO EXPECT SOME SNOW SHOWERS IN THE WESTERLIES ALOFT.

ALU FORECASTS - WIND AND BLOWING SNOW ARE STILL A PROBLEM THIS
MORNING FOR ZONES 155 AND 195 WHERE A PRETTY GOOD NORTH FETCH
PERSISTS. THE SURFACE PRESSURE GRADIENTS ACROSS THIS BAND OF STRONGER
WINDS GRADUALLY WEAKENS INTO THIS EVENING AS A SURFACE RIDGE BUILDS
INTO THE CENTRAL BERING AND THE LOWS IN THE GULF WEAKEN. LOOK FOR A
SHORTWAVE TO BRING IN SOME SNOW SHOWERS MON NIGHT INTO WED ASSOCIATED
WITH THE DEVELOPING WESTERLY FLOW ALOFT. THE NEXT PROBLEM IS A 978 MB
LOW NEAR 45N 170E AT 18Z WHICH SLOWLY MOVES EAST AND WEAKENS AGAINST
THE RIDGE. AN ASSOCIATED FRONT MOVES UP TO THE WESTERN ALEUTIANS
TONIGHT FOR STORM FORCE WINDS THAT THE MODELS HAVE BEEN PREDICTING
FOR DAYS. THIS PATTERN WILL KEEP EASTERLY GALES IN THE ALEUTIANS INTO
WED BUT OFFSHORE FLOW ALONG THE SW COAST. WESTERLIES ALOFT AFTER WED
WILL KEEP THE SW COAST DRIER AND COLDER AS AN UPPER LOW MOVES TO THE
CENTRAL INTERIOR.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...BLOWING SNOW ADVSRY 155 195.
MARINE...STORM 176. HVY FRZ SPRAY 160 179.
         GALES 130 138 170 171 172 175 179 180.
FIRE WEATHER...NONE.

JC JAN 06