Hawaii 30 & 90 Day Narrative
718
FXHW40 KWBC 191231
PMDHCO
PROGNOSTIC DISCUSSION FOR LONG-LEAD HAWAIIAN OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD
830AM EDT THU SEP 19 2013
MONTHLY FORECAST DISCUSSION VALID OCTOBER 2013
SST ANOMALIES NEAR HAWAII ARE NEAR +0.5 DEGREES C NEAR THE NORTHWESTERN
ISLANDS, AND SLIGHTLY LOWER, BUT REMAINING POSITIVE NEAR THE BIG ISLAND.
FOR JANUARY 2013 THROUGH THE END OF AUGUST, RAINFALL TOTAL ACCUMULATIONS WERE:
- LIHUE AIRPORT 17.21 INCHES (80 PERCENT OF NORMAL)
- HONOLULU AIRPORT 9.08 INCHES (102 PERCENT OF NORMAL)
- KAHULUI AIRPORT 8.66 INCHES (81 PERCENT OF NORMAL)
- HILO AIRPORT 54.88 INCHES (81 PERCENT OF NORMAL)
THE CFS SHOWS WEAK INDICATIONS FOR ABOVE NORMAL TEMPERATURES FOR HAWAII. SST
ANOMALIES ARE FORECAST BY THE CFS TO EDGE UPWARD TO AROUND +0.5 DEGREES C IN
OCTOBER. CLIMATE MODELS RUN AS A PART OF THE NATIONAL MULTI-MODEL ENSEMBLE
(NMME) ALSO SUPPORT THIS FORECAST SO THE CHANCES OF ABOVE NORMAL TEMPERATURES
ARE SLIGHTLY ENHANCED FOR OCTOBER, 2013. THERE IS CONSIDERABLE VARIABILITY IN
THE PRECIPITATION FORECAST BETWEEN MODELS INCLUDED IN THE NMME. BELOW MEDIAN
PRECIPITATION IS SLIGHTLY FAVORED AMONG MEMBERS, LEADING TO A FORECAST OF
SLIGHT ELEVATED CHANCES FOR BELOW MEDIAN PRECIPITATION AMOUNTS FOR HAWAII IN
OCTOBER 2013.
TEMPERATURE PRECIPITATION
FCST AVE LIM FCST BLW MEDIAN ABV
HILO A40 75.7 0.5 B40 7.8 8.6 12.1
KAHULUI A40 78.2 0.4 B40 0.3 0.6 1.1
HONOLULU A40 80.2 0.5 B40 0.5 1.3 1.9
LIHUE A40 78.1 0.3 B40 2.5 3.3 4.2
SEASONAL FORECAST DISCUSSION VALID OND 2013 - OND 2014
REFER TO THE 90 DAY DISCUSSION FOR FORECASTS OF EQUATORIAL PACIFIC SST AND
DETAILS OF THE GENERAL BACKGROUND TO THE FORECAST. ENSO-NEUTRAL CONDITIONS
CONTINUE ACROSS THE EQUATORIAL PACIFIC. SEA SURFACE TEMPERATURE ANOMALIES HAVE
RISEN SLIGHTLY IN THE LAST FEW WEEKS IN THE CENTRAL PACIFIC AND ARE NOW VERY
SLIGHTLY POSITIVE. BELOW NORMAL EQUATORIAL SSTS ARE HOLDING ON IN MUCH OF THE
EASTERN PACIFIC ALTHOUGH BELOW NORMAL WATER TEMPERATURES ALONG THE EQUATOR ARE
CONFINED TO A SHALLOW LAYER NEAR THE SURFACE THROUGHOUT THE EASTERN PACIFIC
EXCEPT NEAR THE SOUTH AMERICAN COAST. WINDS AT BOTH LOW AND UPPER LEVELS WERE
CLOSE TO LONG TERM AVERAGES IN AUGUST. CONVECTION REMAINED ENHANCED OVER
INDONESIA AND SUPPRESSED IN THE CENTRAL PART OF THE BASIN. MOST MODEL FORECASTS
INDICATE THAT SSTS THROUGHOUT THE EAST-CENTRAL EQUATORIAL PACIFIC WILL REMAIN
CLOSE TO NORMAL THROUGH AT LEAST EARLY 2014, FAVORING CONTINUED ENSO-NEUTRAL
CONDITIONS.
THE CFS AND NMME SHOW ONLY VERY WEAK INDICATIONS OF CLIMATE ANOMALIES FOR THE
NORTHERN HEMISPHERE FALL AND WINTER. BOTH THE CFS AND NMME PREDICT CONTINUED
POSITIVE SST ANOMALIES NEAR HAWAII FOR OND, WITH MAGNITUDES STRONGEST NEAR THE
NORTHWESTERN ISLANDS, LEADING TO ELEVATED CHANCES FOR ABOVE NORMAL TEMPERATURES
FOR LIHUE AND HONOLULU FOR OND 2013. THERE ARE NO CLEAR INDICATIONS FOR
TEMPERATURE ANOMALIES BEYOND OND, SO EQUAL CHANCES FOR ABOVE, NEAR OR BELOW
NORMAL TEMPERATURES ARE ANTICIPATED AT ALL LOCATIONS FOR LEAD TIMES BEYOND OND
2013.
THE NMME SHOWS ENHANCED CHANCES FOR BELOW MEDIAN PRECIPITATION JUST SOUTH OF
HAWAII FOR OND 2013. SOME HINTS AT DRY CONDITIONS FROM FORECASTS BASED ON SST
CONSTRUCTED ANALOGS AND INDICATIONS FOR BELOW MEDIAN PRECIPITATION FROM THE CCA
LEAD TO A FORECAST FOR ELEVATED CHANCES OF BELOW MEDIAN PRECIPITATION AT HILO.
THE PROBABILISTIC FORECAST FROM THE NMME INDICATES ELEVATED CHANCES FOR BELOW
MEDIAN PRECIPITATION FOR JFM AND FMA 2014, WITH STATISTICAL FORECASTS FROM CCA
EXTENDING THIS SIGNAL INTO MAM 2014 AT HILO.
HILO
TEMPERATURE PRECIPITATION
FCST AVE LIM FCST BLW MEDIAN ABV
OND 2013 EC 75.5 0.4 B40 28.3 34.5 42.0
NDJ 2013 EC 74.2 0.4 EC 26.4 36.6 43.0
DJF 2014 EC 72.8 0.4 EC 19.6 30.2 33.3
JFM 2014 EC 71.8 0.4 B40 22.0 32.0 44.5
FMA 2014 EC 71.7 0.4 B40 24.6 34.1 45.5
MAM 2014 EC 72.0 0.5 B40 22.5 28.4 34.0
AMJ 2014 EC 72.9 0.5 EC 21.4 23.7 29.0
MJJ 2014 EC 74.0 0.4 EC 20.2 27.5 29.1
JJA 2014 EC 75.2 0.4 EC 19.4 27.2 31.4
JAS 2014 EC 76.1 0.4 EC 25.2 28.6 33.4
ASO 2014 EC 76.4 0.4 EC 26.1 28.8 33.3
SON 2014 EC 76.2 0.4 EC 24.3 30.2 40.8
OND 2014 EC 75.5 0.4 EC 28.3 34.5 42.0
KAHULUI
TEMPERATURE PRECIPITATION
FCST AVE LIM FCST BLW MEDIAN ABV
OND 2013 EC 77.8 0.4 EC 4.2 5.3 8.1
NDJ 2013 EC 75.9 0.4 EC 5.2 7.6 9.5
DJF 2014 EC 73.8 0.4 EC 4.6 6.9 8.7
JFM 2014 EC 72.5 0.4 B40 4.2 6.2 8.2
FMA 2014 EC 72.3 0.4 B40 3.2 4.1 6.4
MAM 2014 EC 73.0 0.4 EC 2.5 3.5 4.6
AMJ 2014 EC 74.3 0.5 EC 1.2 1.6 2.2
MJJ 2014 EC 76.0 0.5 EC 0.7 1.1 1.8
JJA 2014 EC 77.7 0.4 EC 0.7 1.1 1.5
JAS 2014 EC 79.0 0.4 EC 0.8 1.1 1.6
ASO 2014 EC 79.4 0.4 EC 0.8 1.6 2.5
SON 2014 EC 79.1 0.4 EC 2.1 3.3 4.8
OND 2014 EC 77.8 0.4 EC 4.2 5.3 8.1
HONOLULU
TEMPERATURE PRECIPITATION
FCST AVE LIM FCST BLW MEDIAN ABV
OND 2013 A40 80.0 0.4 EC 4.4 6.4 8.5
NDJ 2013 EC 77.7 0.5 EC 3.9 5.6 8.8
DJF 2014 EC 75.3 0.5 EC 3.7 5.6 8.6
JFM 2014 EC 73.9 0.4 B40 2.1 4.6 7.8
FMA 2014 EC 73.8 0.4 B40 1.9 3.2 4.7
MAM 2014 EC 74.8 0.4 EC 1.8 2.6 3.0
AMJ 2014 EC 76.3 0.4 EC 1.2 1.6 1.8
MJJ 2014 EC 78.2 0.4 EC 0.8 1.4 1.6
JJA 2014 EC 79.9 0.4 EC 0.7 0.8 1.3
JAS 2014 EC 81.3 0.4 EC 1.0 1.4 1.7
ASO 2014 EC 81.7 0.4 EC 1.6 2.4 3.1
SON 2014 EC 81.4 0.4 EC 2.5 4.0 5.6
OND 2014 EC 80.0 0.4 EC 4.4 6.4 8.5
LIHUE
TEMPERATURE PRECIPITATION
FCST AVE LIM FCST BLW MEDIAN ABV
OND 2013 A40 77.8 0.3 EC 9.2 11.7 15.6
NDJ 2013 EC 75.7 0.3 EC 8.6 12.1 16.9
DJF 2014 EC 73.6 0.4 EC 7.5 8.4 14.0
JFM 2014 EC 72.2 0.4 B40 6.5 8.8 13.8
FMA 2014 EC 72.1 0.5 B40 5.8 8.4 9.9
MAM 2014 EC 72.8 0.5 EC 5.3 6.6 8.0
AMJ 2014 EC 74.2 0.5 EC 4.7 5.5 6.0
MJJ 2014 EC 76.0 0.5 EC 4.9 5.4 5.9
JJA 2014 EC 77.7 0.4 EC 4.4 5.3 6.9
JAS 2014 EC 79.0 0.3 EC 5.3 6.1 7.8
ASO 2014 EC 79.4 0.3 EC 6.2 7.9 8.4
SON 2014 EC 79.1 0.3 EC 9.2 10.0 11.2
OND 2014 EC 77.8 0.3 EC 9.2 11.7 15.6
FORECASTER: DAVID UNGER
ANOMALIES BASED ON 1981-2010 MEANS
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 OCT 17, 2013.