FNUS70 PHFO 181703
FWSHFO

SPOT FORECAST FOR PRESIDENTS DAY...NATIONAL PARK SERVICE
NATIONAL WEATHER SERVICE HONOLULU HI
702 AM HST WED MAR 18 2009

FORECAST IS BASED ON IGNITION TIME OF 0635 HST ON MARCH 18.
IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER
SERVICE.

.DISCUSSION...
THE UPPER LEVEL DISTURBANCE THAT BROUGHT WIDESPREAD RAIN AND
WINTER WEATHER TO THE BIG ISLAND IS NOW WELL NORTHEAST OF THE
STATE. THE BULK OF THE ASSOCIATED SHOWERY WEATHER AND CLOUDINESS
HAS ALSO SHIFTED EAST WHICH WILL ALLOW FOR SOME SUN TO REACH THE
KILAUEA AREA TODAY. THIS MORNING WINDS ARE LIGHT AND VARIABLE
WITH A WELL DEVELOPED NOCTURNAL INVERSION. THIS WILL LIKELY TRAP
PATCHY HIGHER CONCENTRATIONS OF VOG NEAR THE SURFACE EARLY...THEN
BEGIN TO IMPROVE MID TO LATE MORNING AS DAYTIME HEATING BEGINS
AND VERTICAL MIXING INCREASES. HIGH PRESSURE IS STRENGTHENING
NORTH OF STATE. THIS DOES SIGNAL THE IMMINENT RETURN OF TRADE
WINDS...HOWEVER THE EXACT TIMING IS DIFFICULT WITH SOME LEFTOVER
WEAKNESS IN THE LOCAL PRESSURE GRADIENTS STILL POSSIBLE TODAY.
SEA AND LAND BREEZES ARE POSSIBLE THIS AFTERNOON AND
TONIGHT...HOWEVER TRANSPORT FLOW SHOULD BECOME MORE EAST TO
NORTHEAST LATE TODAY INTO TONIGHT. TRADE WINDS WILL BE BACK IN
FULL GEAR FOR THURSDAY.

.TODAY...

SKY/WEATHER.........PARTLY SUNNY. SCATTERED SHOWERS.
MAX TEMPERATURE.....AROUND 69.
MIN HUMIDITY........66 PERCENT.
CHANCE OF PCPN......40 PERCENT.
MIXING HEIGHT.......6500 FT AGL DECREASING TO 4000 FT AGL
                    THIS AFTERNOON.
20-FOOT WINDS.......LIGHT WINDS...BECOMING SOUTHEAST 4 TO 8 MPH
                    LATE THIS MORNING AND THIS AFTERNOON.
TRANSPORT WINDS.....SOUTH AROUND 4 MPH...BECOMING EAST AROUND 8 MPH
                    THIS AFTERNOON.
LAL.................1.

.TONIGHT...

SKY/WEATHER.........PARTLY CLOUDY. SCATTERED SHOWERS.
MIN TEMPERATURE.....AROUND 53.
MAX HUMIDITY........100 PERCENT.
CHANCE OF PCPN......40 PERCENT.
MIXING HEIGHT.......3800 FT AGL.
20-FOOT WINDS.......LIGHT WINDS.
TRANSPORT WINDS.....EAST 7 TO 11 MPH.
LAL.................1.

.THURSDAY...

SKY/WEATHER.........PARTLY SUNNY. SCATTERED SHOWERS.
MAX TEMPERATURE.....AROUND 68.
MIN HUMIDITY........65 PERCENT.
CHANCE OF PCPN......20 PERCENT.
MIXING HEIGHT.......3800-3900 FT AGL.
20-FOOT WINDS.......NORTHEAST WINDS 5 TO 6 MPH.
TRANSPORT WINDS.....EAST AROUND 7 TO 11 MPH.
LAL.................1.

$$
FORECASTER...DEJESUS
REQUESTED BY...HEIDI/NPS
TYPE OF REQUEST...PRESCRIBED .TAG
20090318.PRESI.01/HFO