Small Craft Advisory 597, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
512 AM AKDT TUE OCT 16 2012

.SHORT TERM...EARLY MORNING SATELLITE LOOP SHOWS A LOW...ABOUT
980 MB...OVER THE NORTHERN GULF. A WEAK TROUGH EXTENDS NORTHWEST
ALONG COAST MOUNTAIN RANGE FROM A LOW ACROSS THE CENTRAL BRITISH
COLUMBIA TO A LOW IN THE SOUTHWESTERN YUKON. REMNANTS OF OLD LOW
SLOWLY DRIFT NORTH TO NORTHEAST ACROSS THE EASTERN PANHANDLE. A
WEAK RIDGE OF HIGH PRESSURE SLOWLY BUILDS OVER THE SOUTHEASTERN
GULF AND MAINTAINS SOUTHERLY PRESSURE GRADIENT ACROSS SOUTHEAST
ALASKA WITH SMALL CRAFT WINDS OVER NORTHERN MOST INNER CHANNEL
AND NEAR CAPE DECISION AREA. RAIN SHOWERS CONTINUE OVER THE
FORECAST DOMAIN AND AREAS OF FOG FORM OVER MANY INLAND LOCATIONS.

 MODELS ARE IN GENERAL AGREEMENT WITH THE LOW IN THE NORTHERN
GULF THIS MORNING DRIFTS TO NEAR KENAI PENINSULA THROUGH T0NIGHT
AND WEAKENS TO ABOUT 990 MB. BEHIND OF THE LOW TRACK...A WEAK
RIDGE OF HIGH PRESSURE WILL BUILD OVER SOUTHEAST ALASKA TONIGHT.
THE LOW NEAR KENAI PENINSULA TONIGHT WILL CONTINUE TO WEAKEN AND
MOVE BACK TO THE NORTHERN GULF LATE TONIGHT INTO WEDNESDAY. THE
NAM WAS INITIALIZED BEST AND WAS USED TO REFRESH THE INHERITED
FORECAST PACKAGE FOR TODAY AND TONIGHT.

 AS THE LOW IN THE NORTHERN GULF MOVES NORTHWESTWARD TO NEAR
KENAI PENINSULA...A COLD AIR WILL ENTRAIN OVER THE NORTHEASTERN
GULF COAST TONIGHT. EXPECT RAIN SHOWERS THIS EVENING TURN TO SNOW
SHOWERS OVERNIGHT FOR UP TO 2 INCHES OF ACCUMULATION. SNOW LEVELS
WILL BECOME LOWER TO BELOW 1000 FEET OVER THE NORTHERN AND
CENTRAL PANHANDLE TONIGHT. NEAR GALE FORCE WINDS ACROSS THE
OFFSHORE AND SOUTHERN MOST OUTER WATERS WILL EASE DOWN TO SMALL
CRAFT LEVEL BY MID MORNING AND THE SMALL CRAFT WINDS ACROSS THE
SOUTHERN INNER CHANNELS WILL GRADUALLY SPREAD TO THE NORTHERN
AREAS THROUGH TONIGHT.

&&

.LONG TERM...MODEL SOLUTIONS FOR A LOW THAT WILL APPROACH THE
PANHANDLE FROM THE SOUTH WEDNESDAY AFTERNOON/EVENING HAVE FINALLY
SETTLED DOWN AND ARE CONVERGING ON A TRACK THAT CROSSES THE
SOUTHERN PANHANDLE BEFORE ENTERING CANADA. TRACK, SPEED, AND
CENTRAL PRESSURE DIFFERENCES STILL EXIST AND WILL HAVE SOME
BEARING ON THE SENSIBLE WEATHER, BUT THE SITUATION IS MUCH BETTER
NOW THAN THE PAST FEW NIGHTS. WINDS OVER THE SOUTHERN PANHANDLE
WILL INCREASE THROUGH THE DAY WEDNESDAY AND STRONG WIND HEADLINES
ARE LIKELY FOR PUBLIC ZONES 27 AND 28. A SOUTHEAST GALE IS
FORECAST FOR CLARENCE STRAIT AND SMALL CRAFT ADVISORY WINDS ARE
EXPECTED FOR THE OTHER SOUTHERN INNER CHANNELS. WINDS WILL VERY
ABRUPTLY WEAKEN AND SHIFT DIRECTION AS THE LOW TRACKS INTO CANADA
LATE WEDNESDAY NIGHT.

 LOW LEVEL COLD AIR WILL SPREAD OVER THE EASTERN GULF AND
SOUTHEAST ALASKA BEFORE THE WEDNESDAY LOW AND ITS ASSOCIATED
PRECIPITATION. BELIEVE THERE WILL BE ENOUGH LOW LEVEL WARM AIR
ADVECTION ASSOCIATED WITH THE LOW THAT THE SOUTHERN PANHANDLE WILL
SEE MOSTLY RAIN...POSSIBLY MIXING WITH SNOW LATE AT NIGHT. FARTHER
NORTH, TEMPS WILL REMAIN COLDER AND ACCUMULATING SNOW IS FORECAST
WITH 2 TO 3 INCHES POSSIBLE IN SOME LOCATIONS OVERNIGHT WEDNESDAY
NIGHT.

 BEGINNING THURSDAY, LOW PRESSURE IN THE GULF WILL SLOWLY WEAKEN
AND DRIFT SOUTHEAST. AS THIS HAPPENS, A MODERATE STRENGTH
NORTHERLY PRESSURE GRADIENT WILL SET UP OVER THE PANHANDLE AND THE
INNER CHANNELS AS FAR SOUTH AS FREDERICK SOUND WILL SEE SMALL
CRAFT CONDITIONS BEGINNING FRIDAY NIGHT. THESE CONDITIONS LOOK
LIKE THEY MAY PERSIST THROUGH THE WEEKEND.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING FOR PKZ041.
         SMALL CRAFT ADVISORY FOR PKZ011-012-022-033-036-042-043-051-052.

&&

AHN/FRITSCH