Small Craft Advisory 509, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
200 PM ADT TUE JUN 6 2006

.DISCUSSION...
MODEL INIT AND COMPARISON...MOST OF THE UPPER AIR REPORTS DID NOT
MAKE IT INTO THE NAM THIS MORNING. DESPITE THIS...12Z MODELS SEEM TO
HAVE INITIALIZED WELL THIS MORNING. MODELS IN GOOD AGREEMENT THROUGH
FIRST 60 HOURS. BIG DIFFERENCE STARTS AT THIS TIME FRAME WITH THE
PROGRESSION OF A FRONT AND ASSOCIATED LOW NORTH ALONG 150N. GFS
FASTER WITH THESE FEATURES AS IS THE UKMET AND ECMWF. THIS IS MOST
LIKELY THE RESULT OF A STRONGER JET IS ACCOMPANYING THE LOW IN THESE
MODEL SOLUTIONS. FOR NOW...WILL LEAN TOWARD THESE SOLUTIONS.

UPPER LEVELS...LOW AMPLITUDE RIDGE OVER SOUTH CENTRAL ALASKA WITH A
LOW OVER THE NORTHWEST COAST AND A CUTOFF LOW SOUTH OF THE CENTRAL
ALEUTIANS. THE LOW SOUTH OF THE ALEUTIAN CHAIN TO DEEPEN AS A SHORT
WAVE MOVES INTO IT WITH SOME JET SUPPORT. THIS WILL ACT TO AMPLIFY
RIDGE OVER SOUTH CENTRAL. A PIECE OF THE LOW OVER THE NORTHWEST COAST
TO DROP INTO THE BERING PUSHING THE RIDGE INTO THE WESTERN BERING. BY
THURSDAY EVENING...THE TWO WILL COMBINE JUST SOUTH OF THE EASTERN
ALEUTIAN CHAIN. DURING THIS TIME FRAME THE LOW IN THE NORTHWEST COAST
LIFTS OUT OF ALASKA. THIS LOW DOMINATES THE PATTERN THROUGH THE
WEEKEND AS IT MOVES ACROSS THE ALASKA PENINSULA FRIDAY AND INTO THE
CENTRAL BERING BY SUNDAY.

EAST OF THE ALASKA RANGE...WEAK LOW OVER THE NORTHERN GULF COAST
BRINGING SHOWERS AND ISOLATED THUNDERSTORMS FROM THE CENTRAL PRINCE
WILLIAM SOUND EASTWARD. THIS LOW TO LIFT NORTH ALONG THE COAST WITH
SHOWERS FROM PRINCE WILLIAM SOUND EAST. SHOWERS WILL SPREAD OVER THE
EASTERN COPPER RIVER BASIN AS WELL. THE LOW WILL DISSIPATE TOMORROW
AS HIGH PRESSURE BUILDS OVER THE AREA WITH A FRONT MOVING TO KODIAK.
THE FRONT MOVING ACROSS THE KOSKOKWIM VALLEY TO SKIRT THE UPPER
SUSITNA TOMORROW WITH A FEW SHOWERS OVER THE MOUNTAINS. THE FRONT
WORKS TO THE KENAI PENINSULA THURSDAY AS THE LOW ITSELF CROSSES THE
ALASKA PENINSULA FRIDAY. WINDS OVER THE WATER EXPECTED TO BE GALE
FORCE WITH THE LOW CROSSING THE AKPEN FRIDAY. EXPECT STRONG TURNAGAIN
ARM WINDS TO DEVELOP AS A RESULT FRIDAY AND POSSIBLY THURSDAY NIGHT
AS WELL. THE JET ASSOCIATED WITH THE LOW LIFTS ACROSS SOUTH CENTRAL
FRIDAY NIGHT BRINGING RAIN FARTHER INLAND SATURDAY AND ACROSS THE
COPPER RIVER BASIN. A SECOND FEATURE TO ROTATE AROUND THE LOW AND TO
KODIAK ISLAND SATURDAY NIGHT. THIS WILL PROBABLY BRING A SECOND ROUND
OF TURNAGAIN ARM WINDS.

FIRE WEATHER EAST OF THE ALASKA RANGE...PROFILER DATA AT GLENNALLEN
SHOWING GOOD SOUTHERLY WINDS ABOVE THE SURFACE. EXPECT THESE TO
SURFACE SOON. GIVEN THE DRY AIR MASS OVER SOUTH CENTRAL ALASKA...RED
FLAG CONDITIONS ARE OR WILL BE MET IN THE MAT VALLEY AND COPPER RIVER
BASIN. ALSO MAY SEE IT DEVELOP IN THE SUSITNA VALLEY WITH AN OUTSIDE
CHANCE IN THE ANCHORAGE BOWL. THESE CONDITIONS WILL BE SIMILAR
TOMORROW...SO WILL ISSUE A WATCH FOR THE SAME AREAS TOMORROW.

WEST OF THE ALASKA RANGE...FRONT OVER THE YUKON DELTA AND SLIPPING
SOUTH TO THE KUSKOKWIM DELTA THIS AFTERNOON. DO NOT SEE THE FRONT
SAGGING MUCH FARTHER SOUTH...SO PRECIP CHANCES FOR TONIGHT WILL BE
LOWERED FROM PREVIOUS PACKAGE. FRONT TO DISSIPATE TOMORROW AS A SHORT
WAVE RIDGE MOVES INLAND AHEAD OF A FRONT MOVING TO THE EASTERN
ALEUTIAN CHAIN. WINDS ASSOCIATED WITH THIS INITIAL FRONT NOT EXPECTED
TO EXCEED SMALL CRAFT. FRONT MOVES INTO BRISTOL BAY WEDNESDAY
AFTERNOON BUT NOT MUCH FARTHER WEDNESDAY NIGHT INTO THURSDAY AS A
SECOND LOW DEVELOPS AND ROLLS UP TOWARD KODIAK. THE LOW TO CROSS THE
AKPEN FRIDAY WITH GALE FORCE WINDS FROM CHIGNIK TO SAINT PAUL. PRECIP
TO SPREAD INTO THE REMAINDER OF SOUTHWEST ALASKA AT THIS TIME AS
WELL. HIGH PRESSURE TO REMAIN OVER THE WESTERN BERING SEA. THE LOW
SLOWLY MOVES TO THE CENTRAL ALEUTIAN CHAIN WEAKENING AS THE JET
SUPPORT MOVES THROUGH SOUTH CENTRAL ALASKA. A SECOND WAVE TO MOVE
AROUND THE LOW TOWARD THE AKPEN SATURDAY NIGHT INTO SUNDAY.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE
MARINE...NONE
FIRE WEATHER...RED FLAG TODAY FOR ZONES 111 AND 141

JN JUN 06