Small Craft Advisory 592, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
130 PM AKDT SAT JUL 26 2008

.MODEL DISCUSSION...MODELS ARE IN DECENT AGREEMENT ON SURFACE BROAD
SCALE FEATURES IN THE SHORT TERM BUT ARE HAVING A VERY HARD TIME
DECIPHERING SURFACE DETAILS AND UPPER LEVEL PATTERNS. THE SUMMER
LONG TREND OF WANTING TO PULL A NORTHWEST LOW OUT OF RUSSIA AND DROP
IT FAR SOUTH CONTINUES. RUN-TO-RUN CONSISTENCY HAS BEEN POOR AT BEST.
THEREFORE THERE IS NO MODEL OF CHOICE TODAY.

.ANALYSIS AND UPPER LEVELS...A BROAD LOW SPINNING IN THE GULF OF
ALASKA IS CONTINUING TO BRING RAIN TO THE GULF COAST AND INTO THE
COPPER RIVER VALLEY AS A SERIES OF WAVES MOVES AROUND THE LOW. A
STRONGER WAVE IS CURRENTLY BRINGING STEADY LIGHT RAIN FROM THE
TALKEETNA MOUNTAINS TO THE KENAI PENINSULA. A NARROW FRONTAL BAND IS
MOVING SLOWLY EASTWARD ACROSS THE KUSKOKWIM VALLEY. WESTERLY WINDS
BEHIND IT ARE BRINGING ONSHORE FLOW TO THE MAINLAND WEST COAST AND
ASSOCIATED DRIZZLE..LOW CLOUDS AND FOG. THE NARROW RIDGE OF HIGH
PRESSURE BETWEEN THE SYSTEM IN SOUTHCENTRAL AND THE FRONT MOVING
ACROSS SOUTHWEST AK IS ERODING TO THE POINT WHERE THE TWO AREAS OF
PRECIP ARE ALMOST CONVERGING OVER KODIAK AND THE BARREN ISLANDS.

A RIDGE OF HIGH PRESSURE IS STILL KEEPING FOG AND STRATUS OVER THE
BERING AND THE NORTHERN SIDE OF THE ALEUTIANS. A BROAD AREA OF LOW
PRESSURE MOVING SOUTH OF THE ALEUTIANS IS CAUSING SOME SHOWERS IN THE
CENTRAL AND EASTERN ALEUTIANS.

.SHORT TERM FORECAST...

RAIN AND RAIN SHOWERS WILL CONTINUE ACROSS SOUTHCENTRAL THROUGH
THE WEEKEND AS THE UPPER LEVEL TROUGH AND ITS ASSOCIATED FRONT
CURRENTLY BRINGING RAIN TO THE KUSKOKWIM VALLEY BROADENS AND DROPS
SOUTH ACROSS CENTRAL AK. A LARGE UPPER LEVEL COMPLEX OF LOWS THAT THE
MODELS ARE TRYING TO GET A HANDLE ON WILL DEVELOP ACROSS MAINLAND AK
AND THE GULF THROUGH MON NIGHT.  SURFACE HIGH PRESSURE WILL BUILD
INTO SOUTHWEST AK MON AND MON NIGHT BRINGING LOW CLOUDS AND FOG TO
COASTAL AREAS.

.BERING SEA AND ALEUTIANS..THE RIDGE WILL HOLD THROUGH EARLY NEXT
WEEK KEEPING THE FOG AND STRATUS OVER THE BERING AND BLOCKING ANY
ADVANCEMENT OF LOW PRESSURE SYSTEMS. A COUPLE OF WEAK LOWS WILL MOVE
SOUTH OF THE ALEUTIANS BRINGING SOME RAIN TO THE CENTRAL AND EASTERN
ALEUTIANS THROUGH THE WEEKEND.

.LONG TERM FORECAST...THERE IS STILL A LOT OF UNCERTAINTY IN THE LONG
RANGE MODELS. CONFIDENCE IS EXTREMELY LOW IN ANY MID TO LONG RANGE
SOLUTION BUT THERE DO NOT APPEAR TO BE ANY SIGNIFICANT PATTERN
CHANGES AT THIS TIME.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...ASH FALL ADVISORY ZONE 185.
MARINE...NONE.
FIRE WEATHER...NONE.

RNW JUL 08