Small Craft Advisory 583, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
1215 PM ADT MON JUL 25 2005

.DISCUSSION...

SATELLITE SHOWS THAT THE PLACEMENT OF THE LOW PRESSURE SYSTEM IN THE
NORTHERN PACIFIC IS VERY CLOSE TO WHERE IT WAS YESTERDAY.  ALOFT THE
JET STREAM HAS WEAKENED SLIGHTLY...THE 95KT JET MAX IS NOW IN THE
BASE OF THE TROUGH AND SHOULD BE EXITING TODAY CAUSING THE LOW TO
CONTINUE TO FILL.  THERE IS NO DOUBT ABOUT THE PLACEMENT OF THE
ARCTIC HIGH THIS MORNING AS VISIBLE SATELLITE SHOWS THAT AREAS NORTH
OF THE ALASKA RANGE ARE CLEAR AS A BELL.  THIS STRONG HIGH CENTER
CONTINUES THE HOLDING PATTERN OVER THE STATE...ALTHOUGH AS THE JET
MAX EXITS THE TROUGH THE PATTERN WILL SHIFT A LITTLE. THE LOW WILL
BEGIN TO MOVE EASTWARD THIS EVENING AND MOVE TO THE EASTERN GULF OF
ALASKA BY THURSDAY MORNING.

FORECAST CHALLENGES FOR TODAY HAVE NOT CHANGED MUCH SINCE YESTERDAY.
SOUTHEASTERLY FLOW CONTINUES ACROSS THE SOUTHERN PORTION OF THE STATE
INCLUDING THE SOUTHCENTRAL REGION.  AS THE LOW HAS BECOME LESS
DYNAMIC THE WINDS AND PRECIPITATION ARE LIGHTER THAN YESTERDAY...BUT
THE LOW CENTER IS STILL FAIRLY UNSTABLE AND THE PRECIPITATION HAS
BECOME MORE SHOWERY IN NATURE.  UPPER LEVEL CLOUDS PERVADE THE
SOUTHERN PORTION OF THE STATE...THUNDERSTORMS ARE UNLIKELY FOR MOST
REGIONS SINCE THE LACK OF DAYTIME HEATING WILL NOT CAUSE DAYTIME
HIGHS TO REACH THE CONVECTIVE TEMPERATURE.  THE EXCEPTION IS THE
NORTHERN PORTION OF ZONE 151 WHICH IS STILL BEING AFFECTED BY THE
THERMAL TROUGH ACROSS INTERIOR ALASKA.  NORTHERLY FLOW CONTINUES IN
THE ALEUTIANS.  EXPECT SHOWERS IN THE EASTERN ALEUTIANS SINCE THAT
REGION IS STILL UNDER THE INFLUENCE OF THE UNSTABLE AIR MASS BUT FOG
AND LOW STRATUS SHOULD CONTINUE ADAK AND WESTWARD.

.MODEL DISCUSSION...GFS IS STILL THE PREFERRED MODEL AS ETA IS A
LITTLE STRONG ON THE LOW PRESSURE CENTER SOUTHEAST OF COLD BAY.
ALTHOUGH THE SOLUTIONS DIVERGE SLIGHTLY ON DAY 2 THE END RESULT IS
THE SAME AND THE DIFFERENT SOLUTIONS SHOULD NOT GREATLY IMPACT
FORECASTING FOR THE SOUTHERN REGIONS.

.EXTENDED FORECAST...THE LOW PRESSURE SYSTEM SOUTHWEST OF COLD BAY IS
ALREADY FILLING AND STARTING TO MOVE EASTWARD.  THIS TREND WILL
CONTINUE AS THE LONG WAVE PATTERN SHIFTS SLIGHTLY EAST.  EXPECT
SUNNIER SKIES THURSDAY THROUGH SATURDAY OVER THE SOUTHCENTRAL ZONES
AS THE AIR MASS DRIES OUT.  BE ON THE LOOKOUT FOR AFTERNOON SHOWERS
AND THUNDERSTORMS AS ADEQUATE LOW LEVEL MOISTURE WILL STILL BE
PRESENT AND DAYTIME HEATING INCREASES.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE
MARINE...NONE
FIRE WEATHER...NONE

*** JUL 05