Small Craft Advisory 281, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
200 PM ADT FRI MAR 23 2007

.DISCUSSION...
LARGE LOW COMPLEX IN THE NORTHERN GULF OF ALASKA THIS MORNING
SPREADING SNOWFALL NORTH AND EAST OF AN ANCHORAGE TO SEWARD TO BIG
RIVER LAKES LINE. STRONG WINDS ROTATING AROUND THIS SYSTEM IN THE
GULF AND PRINCE WILLIAM SOUND. A WEAK LOW PRESSURE SYSTEM IS MOVING
INTO THE WESTERN BERING AS WELL WITH HIGH PRESSURE IN BETWEEN. AT THE
UPPER LEVELS THERE IS A LARGE LOW OVER EASTERN SIBERIA WITH A BROAD
TROUGH OVER THE BERING AND MAINLAND.

THE NCEP AND MODELS INITIALIZED OK. HOWEVER...BELIEVE THE NAM HAD
INITIALIZED THE BEST THIS MORNING. MOISTURE FIELDS ARE SLIGHTLY
BETTER AS WELL AS THE PLACEMENT OF THE LOW IN THE NORTHERN GULF.

UPPER LEVELS...THE BROAD TROUGH OVER THE AREA WILL BE REPLACED WITH
THE OMEGA BLOCK ONCE AGAIN BY TUESDAY. IN THE TRANSITION...THE CLOSED
LOW OVER EASTERN SIBERIA TO DROP SOUTHEAST ACROSS THE BERING SUNDAY
AND INTO THE GULF MONDAY. A RIDGE WILL DEVELOP OVER THE BERING FROM
THE WEST MONDAY WITH A LOW MOVING TO THE KAMCHATKA PENINSULA TUESDAY.
THE RIDGE AT THIS TIME WILL BE PLACED OVER THE WESTERN INTERIOR. THE
RIDGE WILL PUSH OVER THE INTERIOR WEDNESDAY WITH THE LOW OVER THE
GULF MOVING TO THE SOUTHERN PANHANDLE AND A BROAD SOUTHWEST FLOW OVER
MUCH OF THE BERING.

WEST OF THE ALASKA RANGE...A WEAK LOW PRESSURE SYSTEM OVER THE
NORTHWEST BERING TO MOVE TO THE YK DELTA SATURDAY AFTERNOON. SNOWFALL
AND MODERATE WINDS WILL ACCOMPANY THIS SYSTEM. A FRONT WILL SWING
THROUGH THE WESTERN ALEUTIANS THIS EVENING THEN CENTRAL BERING
TOMORROW MORNING BEFORE MAKING THE COAST SATURDAY AFTERNOON. THE
FRONT PUSHES INLAND SATURDAY NIGHT BUT WEAKENING AT THE SAME TIME. A
SECONDARY SYSTEM WITH BETTER UPPER LEVEL SUPPORT TO SPIN UP IN THE
BERING SATURDAY NIGHT INTO SUNDAY. DUE TO BETTER UPPER LEVEL
SUPPORT...EXPECT THE WINDS TO BE A BIT STRONG AND MORE PRECIPITATION.
THE LOW WILL CONTINUE TO DEEPEN SUNDAY AS IT MOVES TO BRISTOL BAY.
GALE FORCE WINDS AND GOOD PRECIP AMOUNTS TO HIT FROM THE CENTRAL
ALEUTIANS TO THE AKPEN AND BRISTOL BAY AREA SUNDAY INTO SUNDAY NIGHT.
THE LOW WILL EXIT THE AREA WITH HIGH PRESSURE BUILDING OVER THE
BERING MONDAY. HOWEVER...MODERATE NORTHWEST WINDS TO REMAIN OVER THE
EASTERN BERING THROUGH MONDAY WITH SCATTERED SNOW SHOWERS. A STRONG
LOW TO WORK TOWARD THE KAMCHATKA PENINSULA MONDAY WITH STRONG WINDS
AND WARMING IN THE WESTERN ALEUTIANS AND MODERATE AMOUNTS OF PRECIP.
THE FRONT FROM THIS LOW WILL LIFT NORTH AND EAST INTO WEDNESDAY BUT
WEAKEN AS IT LIFTS. THE GENERAL FLOW IS FROM THE WEST NORTHWEST...SO
TEMPS SHOULD REMAIN SLIGHTLY BELOW NORMAL THROUGH EARLY NEXT WEEK
BEFORE THE WARMER SOUTHWEST FLOW WEDNESDAY.

EAST OF THE ALASKA RANGE...LOW PRESSURE SYSTEM ALONG THE NORTHERN
GULF COAST THIS AFTERNOON TO LIFT NORTH WITH AN UPPER LEVEL
DISTURBANCE THIS EVENING. A RESIDUAL WEAK LOW CENTER TO REMAIN OVER
THE NORTHER GULF. STRONG WINDS MAKING THEIR WAY THROUGH THE GAPS
AROUND THIS LOW. NEAR WHITTIER...THE STRONG WINDS COMBINED WITH
SNOWFALL HAS CREATED BLIZZARD CONDITIONS. THE WINDS WILL LAST LONGER
THAN THE PRECIP...BUT WILL KEEP BLIZZARD INTO THIS EVENING. ANOTHER
UPPER LEVEL DISTURBANCE TO MOVE THROUGH SATURDAY WRINGING OUT MORE
MOISTURE EAST OF ANCHORAGE. THE LOW THAT MOVES INLAND ALONG THE WEST
COAST SUNDAY TO BRING MORE PRECIPITATION TO COASTAL LOCATIONS SUNDAY.
THE STRONGER LOW IN BRISTOL BAY TO CROSS INTO THE GULF SUNDAY NIGHT.
THE JET SUPPORT IS ON THE SOUTH SIDE OF THE SYSTEM. HOWEVER...THERE
IS GOOD WINDS WITH THE UPPER LEVEL TROUGH ASSOCIATED WITH THE SURFACE
LOW. GOOD COLD AIR ADVECTION BEHIND THE SYSTEM FROM SOME STRONG WINDS
TO PUSH ACROSS KODIAK MONDAY. THE SURFACE LOW TO TRACK ACROSS THE
KENAI PENINSULA MONDAY. IF THIS TRACK HOLDS...SNOWFALL WILL BE
PREVALENT OVER MUCH OF SOUTH CENTRAL ALASKA MONDAY. THE LOW AND
ASSOCIATED UPPER LOW SWING QUICKLY TOWARD THE PANHANDLE TUESDAY WITH
PRECIPITATION ENDING OVER SOUTH CENTRAL TUESDAY AFTERNOON. THE PUSH
OF COLD AIR BEHIND THIS UPPER LOW AND RIDGE BUILDING INTO WESTERN
ALASKA WILL MEAN AN INCREASE IN NORTHERLY WINDS ESPECIALLY THROUGH
THE GAPS. HIGH PRESSURE TO REMAIN OVER THE AREA THROUGH THURSDAY.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...BLIZZARD WARNING ZONE 125
MARINE...HEAVY FREEZING SPRAY...ZONES 121 129 130 141 150
         GALE...ZONES 129 130 172 175
FIRE WEATHER...NONE

JN MAR 07