991  
FXHW40 KWBC 211243  
PMDHCO  
PROGNOSTIC DISCUSSION FOR LONG-LEAD HAWAIIAN OUTLOOKS  
NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD  
830AM EDT THU AUG 21 2008  
 
MONTHLY FORECAST DISCUSSION VALID FOR SEPTEMBER 2008  
 
SST ANOMALIES NEAR HAWAII NOW AROUND ZERO DEGREE C.  
 
FOR JANUARY 2008 THROUGH THE END OF JULY - RAINFALL TOTAL ACCUMULATIONS WERE:  
 
- LIHUE AIRPORT 8.41 INCHES (39 PERCENT OF NORMAL)  
 
- HONOLULU AIRPORT 2.79 INCHES (28 PERCENT OF NORMAL)  
 
- KAHULUI AIRPORT 3.09 INCHES (26 PERCENT OF NORMAL)  
 
- HILO AIRPORT 76.87 INCHES (106 PERCENT OF NORMAL).  
 
NCEP MODELS PREDICT BELOW NORMAL TEMPERATURE AND BELOW NORMAL PRECIPITATION FOR  
HAWAII FOR SEPTEMBER 2008.  
TEMPERATURE PRECIPITATION  
FCST AVE LIM FCST BLW MEDIAN ABV  
HILO B40 76.4 0.5 B40 5.4 8.7 9.9  
KAHULUI B40 79.2 0.6 B40 0.1 0.2 0.3  
HONOLULU B40 81.4 0.5 B40 0.4 0.5 0.9  
LIHUE B40 79.4 0.3 B40 1.4 1.8 2.0  
 
SEASONAL OUTLOOK DISCUSSION VALID FOR SON 2008 TO SON 2009  
 
REFER TO THE 90 DAY DISCUSSION FOR FORECASTS OF EQUATORIAL PACIFIC SST AND  
 
DETAILS OF THE GENERAL BACKGROUND TO THE FORECAST. ENSO-NEUTRAL CONDITIONS ARE  
PRESENT IN THE EQUATORIAL PACIFIC OCEAN. EQUATORIAL SSTS IN THE CENTRAL PACIFIC  
OCEAN HAVE RETURNED TO NEAR-AVERAGE - WHILE POSITIVE SST ANOMALIES CONTINUE IN  
THE EASTERN PACIFIC. WARM SUB-SURFACE ANOMALIES HAVE NOW MODERATED ACROSS THE  
PACIFIC BASIN. THE ATMOSPHERIC CIRCULATION OVER THE WESTERN AND CENTRAL  
TROPICAL PACIFIC CONTINUES TO REFLECT SOME ASPECTS OF LA NIA. ENHANCED  
LOW-LEVEL EASTERLY WINDS AND UPPER-LEVEL WESTERLY WINDS PERSIST IN THIS REGION  
- WHILE CONVECTION REMAINS GENERALLY SUPPRESSED OVER THE CENTRAL PACIFIC.  
DESPITE RECENT INCREASES IN SST ANOMALIES - THE ACTUAL SSTS ARE NOT WARM ENOUGH  
TO SUPPORT CONVECTION. BASED ON CURRENT ATMOSPHERIC AND OCEANIC CONDITIONS -  
RECENT TRENDS - AND MODEL FORECASTS - ENSO-NEUTRAL CONDITIONS ARE EXPECTED TO  
CONTINUE THROUGH THE NORTHERN HEMISPHERE FALL 2008.  
 
NCEP MODELS PREDICT A TENDENCY FOR BELOW NORMAL TEMPERATURE FOR HAWAII FROM SON  
TO OND 2008. MODELS ALSO PREDICT BELOW NORMAL PRECIPITATION FOR HAWAII FROM SON  
TO OND 2008.  
HILO  
TEMPERATURE PRECIPITATION  
FCST AVE LIM FCST BLW MEDIAN ABV  
SON 2008 B40 75.5 0.4 B45 25.8 31.7 38.4  
OND 2008 B40 74.2 0.4 B45 26.1 33.1 41.3  
NDJ 2008 EC 72.8 0.4 EC 25.5 32.9 41.7  
DJF 2008 EC 72.0 0.4 EC 20.1 27.2 35.9  
JFM 2009 EC 71.8 0.4 EC 23.9 30.9 39.4  
FMA 2009 EC 72.1 0.4 EC 29.5 35.9 43.1  
MAM 2009 EC 72.8 0.5 EC 28.3 34.9 42.6  
AMJ 2009 EC 73.9 0.4 EC 22.0 26.8 32.2  
MJJ 2009 EC 75.0 0.4 EC 19.1 23.1 27.8  
JJA 2009 EC 75.9 0.4 EC 19.5 24.2 29.6  
JAS 2009 EC 76.3 0.4 EC 22.2 27.1 32.7  
ASO 2009 EC 76.2 0.4 EC 23.4 27.0 31.0  
SON 2009 EC 75.5 0.4 EC 25.8 31.7 38.4  
KAHULUI  
TEMPERATURE PRECIPITATION  
FCST AVE LIM FCST BLW MEDIAN ABV  
SON 2008 B40 77.8 0.5 B45 2.2 3.1 4.3  
OND 2008 B40 75.9 0.5 B45 4.2 5.7 7.6  
NDJ 2008 EC 73.8 0.5 EC 5.7 7.8 10.4  
DJF 2008 EC 72.5 0.5 EC 6.8 9.0 11.7  
JFM 2009 EC 72.4 0.5 EC 6.0 8.1 10.6  
FMA 2009 EC 73.2 0.5 EC 4.3 6.0 8.1  
MAM 2009 EC 74.4 0.6 EC 2.9 4.2 5.8  
AMJ 2009 EC 75.8 0.6 EC 1.0 1.8 3.1  
MJJ 2009 EC 77.3 0.6 EC 0.7 1.1 1.5  
JJA 2009 EC 78.6 0.5 EC 0.8 1.1 1.3  
JAS 2009 EC 79.1 0.5 EC 0.9 1.2 1.5  
ASO 2009 EC 78.9 0.5 EC 1.3 1.8 2.5  
SON 2009 EC 77.8 0.5 EC 2.2 3.1 4.3  
 
HONOLULU  
TEMPERATURE PRECIPITATION  
FCST AVE LIM FCST BLW MEDIAN ABV  
SON 2008 B40 79.6 0.5 B45 2.7 4.0 5.9  
OND 2008 B40 77.3 0.5 B45 4.5 6.2 8.4  
NDJ 2008 EC 73.8 0.5 EC 5.7 7.8 10.4  
DJF 2008 EC 73.5 0.4 EC 5.0 6.9 9.1  
JFM 2009 EC 73.5 0.4 EC 4.1 5.8 8.0  
FMA 2009 EC 74.5 0.4 EC 3.4 4.6 6.1  
MAM 2009 EC 76.0 0.4 EC 2.4 3.2 4.3  
AMJ 2009 EC 77.7 0.4 EC 1.2 1.8 2.6  
MJJ 2009 EC 79.3 0.4 EC 1.0 1.4 2.0  
JJA 2009 EC 80.7 0.4 EC 0.8 1.2 1.6  
JAS 2009 EC 81.2 0.4 EC 1.1 1.5 2.0  
ASO 2009 EC 81.0 0.5 EC 1.7 2.6 3.8  
SON 2009 EC 79.6 0.5 EC 2.7 4.0 5.9  
 
LIHUE  
TEMPERATURE PRECIPITATION  
FCST AVE LIM FCST BLW MEDIAN ABV  
SON 2008 B40 77.7 0.3 B45 9.1 10.9 12.9  
OND 2008 B40 75.6 0.3 B45 10.7 13.3 16.2  
NDJ 2008 EC 73.6 0.3 EC 9.8 12.5 15.8  
DJF 2008 EC 72.4 0.4 EC 8.6 11.4 14.7  
JFM 2009 EC 72.4 0.4 EC 8.0 10.8 14.1  
FMA 2009 EC 73.1 0.4 EC 7.5 9.6 12.0  
MAM 2009 EC 74.4 0.4 EC 7.3 9.2 11.4  
AMJ 2009 EC 75.9 0.4 EC 5.3 7.0 9.0  
MJJ 2009 EC 77.5 0.4 EC 4.6 6.2 8.0  
JJA 2009 EC 78.8 0.3 EC 4.6 5.6 6.6  
JAS 2009 EC 79.3 0.3 EC 5.1 6.2 7.4  
ASO 2009 EC 79.0 0.3 EC 6.3 8.0 10.0  
SON 2009 EC 77.7 0.3 EC 9.1 10.9 12.9  
 
FORECASTER: LUKE HE  
 
NOTE - ON SEPTEMBER 18 2003...THE CLIMATE PREDICTION CENTER (CPC) MADE A CHANGE  
TO PROBABILITIES EXPRESSED FOR THE ABOVE NORMAL...NEAR NORMAL...AND BELOW  
NORMAL CATEGORIES IN ONE-MONTH AND THREE-MONTH OUTLOOKS. CPC WILL NO LONGER  
EXPRESS PROBABILITIES AS ANOMALIES FROM 33 PERCENT. INSTEAD WE USE THE ACTUAL  
PROBABILITES FOR THE CATEGORIES. PLEASE SEE THE FOLLOWING LINK FOR MORE DETAILS:  
 
HTTP://WWW.CPC.NCEP.NOAA.GOV/PRODUCTS/PREDICTIONS/90DAY/SERVICE_CHANGE_LL.HTML  
 
NOTE - EC (EQUAL CHANCES) HAS REPLACED CL (CLIMATOLOGICAL PROBABILITIES) AT  
THOSE LOCATIONS WHERE THE FORECAST IS UNCERTAIN.  
 
CLARIFICATION: EC INDICATES EQUAL CHANCES THAT THE CLIMATE WILL FALL INTO ANY  
ONE OF THE THREE RANGES OR CATEGORIES WHOSE BOUNDARIES ARE SPECIFIED IN THE  
TABLES ABOVE. A FORECAST SPECIFICATION OF EC MEANS THERE IS NO PARTICULAR TILT  
OF THE ODDS TOWARD ABOVE - NORMAL - OR BELOW NORMAL CONDITIONS IN THE OUTLOOK.  
FOR EXAMPLE -A37 MEANS A 37% CHANCE THAT TEMPERATURE OR PRECIPITATION WILL BE  
IN THE ABOVE CLASS - B36 MEANS A 36% PROBABILITY THAT TEMPERATURE OR  
PRECIPITATION WILL BE IN THE BELOW CLASS - AND N35 MEANS A 35% PROBABILITY THAT  
TEMPERATURE OR PRECIPITATION WILL BE IN THE NEAR NORMAL CLASS. WHEN EC IS  
SPECIFIED THE PROBABILITY OF THE MOST LIKELY CATEGORY CANNOT BE PREDICTED.  
 
NOTE - THESE OUTLOOKS ARE INTENDED FOR USE PRIOR TO THE START OF THEIR VALID  
PERIODS. WITHIN ANY VALID PERIOD OBSERVATIONS AND SHORTER RANGE FORECASTS  
SHOULD BE CONSULTED. ALSO - THIS SET OF OUTLOOKS WILL BE SUPERSEDED BY THE  
ISSUANCE OF THE NEW SET NEXT MONTH ON THU SEP 18, 2008  
 
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