Hawaii 30 & 90 Day Narrative

240 
FXHW40 KWBC 201230
PMDHCO
PROGNOSTIC DISCUSSION FOR LONG-LEAD HAWAIIAN OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD
830AM EDT THU JUL 20 2017
MONTHLY FORECAST DISCUSSION VALID AUGUST 2017
SEA SURFACE TEMPERATURE (SST) ANOMALIES SURROUNDING THE HAWAIIAN ISLANDS ARE
CURRENTLY BETWEEN ZERO DEGREE TO POSITIVE TWO DEGREE C, WITH HIGHER ANOMALIES 
NEAR THE NORTHWEST ISLANDS.
FOR JANUARY 2017 THROUGH THE END OF JUNE 2017, RAINFALL TOTAL ACCUMULATIONS 
WERE:
- LIHUE AIRPORT 15.45 INCHES (89 PERCENT OF NORMAL)
- HONOLULU AIRPORT 14.02 INCHES (179 PERCENT OF NORMAL)
- KAHULUI AIRPORT 14.59 INCHES (150 PERCENT OF NORMAL)
- HILO AIRPORT 37.60 INCHES (63 PERCENT OF NORMAL)
THE NCEP CLIMATE FORECAST SYSTEM (CFS) AND OTHER CLIMATE MODELS RUN AS A PART 
OF THE NORTH AMERICAN MULTI-MODEL ENSEMBLE (NMME) PREDICT ABOVE NORMAL SSTS 
AROUND THE HAWAIIAN ISLANDS. THIS ELEVATES THE CHANCES OF ABOVE-NORMAL MONTHLY 
MEAN AIR TEMPERATURES FOR THE HAWAIIAN ISLANDS IN AUGUST 2017. EQUAL CHANCES 
(EC) FOR ABOVE, NEAR, OR BELOW MEDIAN PRECIPITATION ARE ALSO INDICATED BY MOST 
DYNAMICAL MODEL FORECASTS FOR HAWAII DURING AUGUST 2017. 
           TEMPERATURE           PRECIPITATION
          FCST   AVE    LIM  FCST  BLW  MEDIAN  ABV
HILO       A60   76.6   0.4   EC   7.6   8.4   10.3
KAHULUI    A60   79.8   0.4   EC   0.3   0.5   0.6
HONOLULU   A60   82.1   0.4   EC   0.1   0.2   0.4
LIHUE      A60   79.7   0.4   EC   1.4   1.8   2.5
SEASONAL FORECAST DISCUSSION VALID ASO 2017 - ASO 2018
REFER TO THE PROGNOSTIC DISCUSSION ON LONG-LEAD SEASONAL OUTLOOKS FOR THE CONUS 
AND ALASKA, AND DISCUSSION OF THE FORECASTS OF EQUATORIAL PACIFIC SSTS, FOR THE 
GENERAL BACKGROUND FOR THE SEASONAL FORECAST, INCLUDING DETAILS ON THE CURRENT 
STATE OF THE ATMOSPHERE AND OCEAN. ENSO-NEUTRAL CONDITIONS CURRENTLY ARE 
PRESENT ACROSS THE EQUATORIAL PACIFIC OCEAN. EQUATORIAL SEA SURFACE 
TEMPERATURES (SSTS) WERE ABOVE-AVERAGE ACROSS THE WESTERN TO EAST-CENTRAL 
PACIFIC, WHILE NEAR-AVERAGE SSTS WERE MEASURED IN THE EASTERN PACIFIC. POSITIVE 
SUBSURFACE TEMPERATURE ANOMALIES HAVE EXPANDED JUST BELOW THE SURFACE NEAR140 W 
AND CONTINUE TO PERSIST ACROSS MOST OF THE EQUATORIAL PACIFIC. ATMOSPHERIC 
CONVECTION ANOMALIES WERE SUPPRESSED OVER THE WEST-CENTRAL TROPICAL PACIFIC, 
WHILE THE LOWER-LEVEL AND UPPER-LEVEL WINDS WERE NEAR AVERAGE OVER MOST OF THE 
TROPICAL PACIFIC OCEAN. THE NCEP CFSV2 AND MOST OF THE MODELS FROM THE LATEST 
RUNS OF THE NMME ARE NOW FAVORING THE CONTINUATION OF ENSO-NEUTRAL THROUGH THE 
REMAINDER OF 2017. IN THE OFFICIAL OUTLOOK, ENSO-NEUTRAL IS FAVORED (ABOUT 50 
TO 55% CHANCE) THROUGH THE NORTHERN HEMISPHERE WINTER 2017-18.
ENHANCED PROBABILITIES FOR ABOVE-NORMAL TEMPERATURES ARE INDICATED FOR HAWAII 
FROM ASO 2017 TO DJF 2018 DUE TO PREDICTED ANOMALOUSLY ABOVE-NORMAL SEA SURFACE 
TEMPERATURES ACROSS THE REGION. EQUAL CHANCES (EC) FOR ABOVE, NEAR, OR BELOW 
NORMAL TEMPERATURES ARE ANTICIPATED AT ALL LOCATIONS FOR JFM 2018 AND BEYOND.
THERE IS HIGH UNCERTAINTY WITH THE PRECIPITATION FORECAST FOR HAWAII FROM ASO 
TO NDJ 2017. EQUAL CHANCES (EC) FOR ABOVE, NEAR, OR BELOW MEDIAN PRECIPITATION 
ARE INDICATED BY MOST DYNAMICAL MODEL FORECASTS AND NMME FOR HAWAII FROM ASO TO 
NDJ 2017. CPC CONSTRUCTED ANALOG (CA) TOOL FAVORS BELOW MEDIAN PRECIPITATION 
FOR LIHUE , HONOLULU, KAHULUI FOR THE INCOMING WINTER SEASONS FROM DJF TO JFM 
2018. EQUAL CHANCES (EC) FOR ABOVE, NEAR, OR BELOW MEDIAN PRECIPITATION ARE 
FORECAST FOR HAWAII IN FMA 2018 AND LONGER LEADS.
                      HILO
          TEMPERATURE           PRECIPITATION
         FCST   AVE   LIM  FCST   BLW  MEDIAN   ABV
ASO 2017  A65  76.4   0.4    EC   26.1   28.8   33.3
SON 2017  A60  76.2   0.4    EC   24.3   30.2   40.8
OND 2017  A60  75.5   0.4    EC   28.3   34.5   42.0
NDJ 2017  A55  74.2   0.4    EC   26.4   36.6   43.0
DJF 2018  A45  72.8   0.4    EC   19.6   30.2   33.3
JFM 2018   EC  71.8   0.4    EC   22.0   32.0   44.5
FMA 2018   EC  71.7   0.4    EC   24.6   34.1   45.5
MAM 2018   EC  72.0   0.5    EC   22.5   28.4   34.0
AMJ 2018   EC  72.9   0.5    EC   21.4   23.7   29.0
MJJ 2018   EC  74.0   0.4    EC   20.2   27.5   29.1
JJA 2018   EC  75.2   0.4    EC   19.4   27.2   31.4
JAS 2018   EC  76.1   0.4    EC   25.2   28.6   33.4
ASO 2018   EC  76.4   0.4    EC   26.1   28.8   33.3
\N                      KAHULUI
          TEMPERATURE           PRECIPITATION
         FCST   AVE   LIM  FCST   BLW  MEDIAN   ABV
ASO 2017  A65  79.4   0.4    EC   0.8    1.6    2.5 
SON 2017  A60  79.1   0.4    EC   2.1    3.3    4.8 
OND 2017  A60  77.8   0.4    EC   4.2    5.3    8.1 
NDJ 2017  A55  75.9   0.4    EC   5.2    7.6    9.5 
DJF 2018  A45  73.8   0.4   B40   4.6    6.9    8.7 
JFM 2018   EC  72.5   0.4   B40   4.2    6.2    8.2 
FMA 2018   EC  72.3   0.4    EC   3.2    4.1    6.4 
MAM 2018   EC  73.0   0.4    EC   2.5    3.5    4.6 
AMJ 2018   EC  74.3   0.5    EC   1.2    1.6    2.2 
MJJ 2018   EC  76.0   0.5    EC   0.7    1.1    1.8 
JJA 2018   EC  77.7   0.4    EC   0.7    1.1    1.5 
JAS 2018   EC  79.0   0.4    EC   0.8    1.1    1.6 
ASO 2018   EC  79.4   0.4    EC   0.8    1.6    2.5 
\N                      HONOLULU
          TEMPERATURE           PRECIPITATION
         FCST   AVE   LIM  FCST   BLW  MEDIAN   ABV
ASO 2017  A70  81.7   0.4    EC   1.6    2.4    3.1 
SON 2017  A65  81.4   0.4    EC   2.5    4.0    5.6 
OND 2017  A60  80.0   0.4    EC   4.4    6.4    8.5 
NDJ 2017  A55  77.7   0.5    EC   3.9    5.6    8.8 
DJF 2018  A45  75.3   0.5   B40   3.7    5.6    8.6 
JFM 2018   EC  73.9   0.4   B40   2.1    4.6    7.8 
FMA 2018   EC  73.8   0.4    EC   1.9    3.2    4.7 
MAM 2018   EC  74.8   0.4    EC   1.8    2.6    3.0 
AMJ 2018   EC  76.3   0.4    EC   1.2    1.6    1.8 
MJJ 2018   EC  78.2   0.4    EC   0.8    1.4    1.6 
JJA 2018   EC  79.9   0.4    EC   0.7    0.8    1.3 
JAS 2018   EC  81.3   0.4    EC   1.0    1.4    1.7 
ASO 2018   EC  81.7   0.4    EC   1.6    2.4    3.1 
\N                      LIHUE
          TEMPERATURE           PRECIPITATION
         FCST   AVE   LIM  FCST   BLW  MEDIAN   ABV
ASO 2017  A70  79.4   0.3    EC   6.2    7.9    8.4 
SON 2017  A65  79.1   0.3    EC   9.2    10.0   11.2
OND 2017  A65  77.8   0.3    EC   9.2    11.7   15.6
NDJ 2017  A60  75.7   0.3    EC   8.6    12.1   16.9
DJF 2018  A50  73.6   0.4   B40   7.5    8.4    14.0
JFM 2018   EC  72.2   0.4   B40   6.5    8.8    13.8
FMA 2018   EC  72.1   0.5    EC   5.8    8.4    9.9 
MAM 2018   EC  72.8   0.5    EC   5.3    6.6    8.0 
AMJ 2018   EC  74.2   0.5    EC   4.7    5.5    6.0 
MJJ 2018   EC  76.0   0.5    EC   4.9    5.4    5.9 
JJA 2018   EC  77.7   0.4    EC   4.4    5.3    6.9 
JAS 2018   EC  79.0   0.3    EC   5.3    6.1    7.8 
ASO 2018   EC  79.4   0.3    EC   6.2    7.9    8.4 
\NFORECASTER: LUKE HE
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 A40 MEANS A 40% CHANCE THAT TEMPERATURE OR PRECIPITATION WILL BE IN THE 
ABOVE CLASS, B40 MEANS A 40% 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, ALL 
CATEGORIES ARE EQUALLY LIKELY.
 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 AUG 17, 2017.
$$