Small Craft Advisory 358, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
500 PM ADT SAT APR 23 2005

.DISCUSSION...
ANALYSIS - THE UPPER HIGH IS BUILDING OVER THE PANHANDLE. THE SETS UP
A LONG FETCH BUT ANTICYCLONIC SOUTHERLY FLOW ALOFT CENTERED AROUND
150W THIS MORNING. THE FOCUS OF THE MOISTURE HAS SHIFTED W TO OVER
COOK INLET THIS MORNING ALONG A WEAKENING FRONT UNDER THE JET. AN
UPPER LOW HAS DEVELOPED NEAR 47N 157W SUPPORTING A 1011 MB LOW S OF
KODIAK AND A SECOND LOW AROUND 1013 MB NEAR 45N 153W MOVING RAPIDLY
E. A STORM HAS DEVELOPED AROUND 970 MB NEAR 45N 170E AT 12Z WITH THE
OCCLUDED FRONT ABOUT 180 AND LOTS OF WARM ADVECTION AHEAD OF IT. A
SURFACE RIDGE IS OVER THE EASTERN ALEUTIANS AND AKPENN. THE
ANTICYCLONIC JET CORE IS 125 KT AT 250 MB 12Z BETWEEN PAMC AND PANC.
THE SUBTROPICAL JET IS WEST OFF JAPAN AT 170 KT ALONG 38N OR SO.

AER FORECASTS - THE OLD FRONT WITH THE JET OVER IT IS TAKING ITS TIME
EXITING THE AREA ALTHOUGH IT HAS SLOWLY MOVED WEST. LOW LEVEL
MOISTURE IS CAUSING PATCHY LOW CLOUDS AND FOG THAT WILL LIFT THIS
AFTERNOON BUT SHOULD REAPPEAR LATER TONIGHT WITH EXTENSIVE RADIATION
IN CLEAR TO PARTLY CLOUDY SKIES. SUNDAY WILL BE NICE DUE TO A LACK OF
UPPER LEVEL MOISTURE PLUS SOME SUBSIDENCE DUE TO THE UPPER HIGH
BUILDING. IN THE MEDIUM RANGE LOOK FOR MUCH WARMER TEMPS AND DRY DRY
DRY CONDITIONS AS THE UPPER HIGH MOVES OVER S CENTRAL. SEVERAL MODEL
RUNS ALL FORECAST THIS SCENARIO. COULD BE RECORD HIGH TEMPS LATER IN
THE WEEK.

ALU FORECASTS - THANKS TO THE STRONG FRONT APPROACHING THE BIG STORY
WILL BE WIND. WE PREFER THE TIMING OF THE GFS-190 WHICH BRINGS THE
LOW CENTER TO AMCHITKA AT 973 MB 12Z SUN WITH THE FRONT NEAR
UNALASKA. PRES GRADIENTS WEAKEN SIGNIFICANTLY AS THE FRONT MOVES TO
COLD BAY BY 00Z MON AND OFF NUNIVAK ISLAND. WITH THE BLOCK EAST IN
THE MEDIUM RANGE WE EXPECT THAT A SERIES OF LOWS WILL MOVE INTO THE
BERING THROUGH THE WEEK WITH GALES ON THE FRONTS.

.AER/ALU...WATCH/WARNING SUMMARY AS OF 11 AM
PUBLIC...WIND ADVSRY 101 185 187 191 195.
MARINE...STORM 172 175 176. GALES 165 170 171 179 180 185.
         HVY FRZ SPRAY 180 185.
FIRE WEATHER...NONE.

JC APR 05