Climate Prediction Center - Seasonal Outlook

Prognostic Discussion for Long-Lead Hawaiian Outlooks 
NWS Climate Prediction Center College Park MD 
830AM EST Thu Feb 20 2020 
 
MONTHLY FORECAST DISCUSSION VALID MARCH 2020 
 
Sea surface temperature (SST) anomalies are about positive one half to one degree Celsius surrounding the Hawaiian Islands during the previous week. 
 
For January 2020, rainfall total accumulations were: 
 
- Lihue Airport 1.60 inches (43 percent of normal) 
- Honolulu Airport 1.13 inches (49 percent of normal) 
- Kahului Airport 2.86 Inches (100 percent of normal) 
- Hilo Airport 15.89 Inches (172 percent of normal) 
 
The NCEP Climate Forecast System (CFS) and other climate models of the North American Multi-Model Ensemble (NMME) predict above normal SSTs around the Hawaiian Islands for March 2020. Model guidance from the NMME indicates anomalies of one-half to one degree Celsius above normal are expected to continue. This elevates the chances of above normal monthly mean air temperatures for Hawaii in March 2020. Most dynamical models  from the NMME predict above normal precipitation over the Hawaiian Islands during March 2020. 
 
 
 





  TEMPERATURE   PRECIPITATION
    FCST  AVE  LIM  FCST  BLW  MEDIAN  ABV
 Hilo  A65  72.0  0.6  A45  5.7  10.8  15.2
 Kahului  A65  72.9  0.5  A45  1.4  1.9  2.9
 Honolulu  A65  74.7  0.5  A45  0.6  0.8  1.9
 Lihue  A65  72.7  0.6  A45  1.9  2.6  3.6
 
 
SEASONAL FORECAST DISCUSSION VALID MAM 2020 - MAM 2021 
 
Refer to the prognostic discussion of the long-lead seasonal outlooks for the CONUS and Alaska for a discussion of the ENSO outlook and other climate conditions relevant to the seasonal outlook, 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) are near to above average across the Pacific Ocean and positive SST anomalies are largest near the Date Line, exceeding +1.0 degree Celsius. Subsurface temperature anomalies remain positive across most of the Pacific Ocean near the surface, reaching depths greater than 150 meters near the Date Line, while negative subsurface temperature anomalies have emerged below 100 meters depth in the western Pacific. Tropical convection is suppressed over the Maritime Continent and is enhanced near the Date Line. ENSO-neutral is likely to continue through Northern Hemisphere spring 2020 with probabilities about 60 percent and through summer 2020 with probabilities about 50 percent. 
 
Enhanced probabilities for above normal temperatures are indicated across the Hawaiian Islands in the outlook from MAM 2020 to JAS 2020, due to predicted persistence of above normal sea surface temperatures in the NMME dynamical model forecasts, and supported by statistical models including the Constructed Analog (CA) and Optimum Climate Normals (OCN) through ASO 2020. The signal weakens at longer leads, therefore Equal Chances (EC) for above, near or below normal temperatures are indicated for Hawaii in SON 2020 and thereafter. 
 
Most dynamical models  and probability forecasts from the NMME predict above normal precipitation over the Hawaiian Islands in MAM 2020. Dynamical models  from the NMME have mixed signals  in AMJ 2020 through JJA 2020, while predicting above normal precipitation over the southeastern Hawaiian Islands in JAS 2020. The Constructed Analog (CA) predicts persistent above normal precipitation over parts of the Hawaiian Islands for MAM 2020 through JAS 2020, with stronger signals  over the southeastern islands. Enhanced probabilities for above normal precipitation are indicated in the outlook from MAM 2020 to JAS 2020 for the southeastern islands and from MAM 2020 to MJJ 2020 for the northwestern islands. There is considerable uncertainty in the precipitation forecast among available dynamical and statistical tools over Hilo and Kahului in ASO 2020 and longer leads and over Honolulu and Lihue in JJA 2020 and longer leads, so equal chances (EC) for above, near or below normal precipitation are indicated. 
 
 
















 Hilo
  TEMPERATURE  PRECIPITATION
    FCST  AVE  LIM  FCST  BLW  MEDIAN  ABV
 MAM 2020  A65  72.0  0.5  A45  22.5  28.4  34.0
 AMJ 2020  A60  72.9  0.5  A45  21.4  23.7  29.0
 MJJ 2020  A55  74.0  0.4  A40  20.2  27.5  29.1
 JJA 2020  A50  75.2  0.4  A40  19.4  27.2  31.4
 JAS 2020  A45  76.1  0.4  A40  25.2  28.6  33.4
 ASO 2020  A40  76.4  0.4   EC  26.1  28.8  33.3
 SON 2020   EC  76.2  0.4   EC  24.3  30.2  40.8
 OND 2020   EC  75.5  0.4   EC  28.3  34.5  42.0
 NDJ 2020   EC  74.2  0.4   EC  26.4  36.6  43.0
 DJF 2021   EC  72.8  0.4   EC  19.6  30.2  33.3
 JFM 2021   EC  71.8  0.4   EC  22.0  32.0  44.5
 FMA 2021   EC  71.7  0.4   EC  24.6  34.1  45.5
 MAM 2021   EC  72.0  0.5   EC  22.5  28.4  34.0
 

















 Kahului
  TEMPERATURE  PRECIPITATION
    FCST  AVE  LIM  FCST  BLW  MEDIAN  ABV
 MAM 2020  A65  73.0  0.4  A45  2.5  3.5  4.6 
 AMJ 2020  A60  74.3  0.5  A45  1.2  1.6  2.2 
 MJJ 2020  A55  76.0  0.5  A40  0.7  1.1  1.8 
 JJA 2020  A50  77.7  0.4  A40  0.7  1.1  1.5 
 JAS 2020  A45  79.0  0.4  A40  0.8  1.1  1.6 
 ASO 2020  A40  79.4  0.4   EC  0.8  1.6  2.5 
 SON 2020   EC  79.1  0.4   EC  2.1  3.3  4.8 
 OND 2020   EC  77.8  0.4   EC  4.2  5.3  8.1 
 NDJ 2020   EC  75.9  0.4   EC  5.2  7.6  9.5 
 DJF 2021   EC  73.8  0.4   EC  4.6  6.9  8.7 
 JFM 2021   EC  72.5  0.4   EC  4.2  6.2  8.2 
 FMA 2021   EC  72.3  0.4   EC  3.2  4.1  6.4 
 MAM 2021   EC  73.0  0.4   EC  2.5  3.5  4.6 
 

















 Honolulu
  TEMPERATURE  PRECIPITATION
    FCST  AVE  LIM  FCST  BLW  MEDIAN  ABV
 MAM 2020  A65  74.8  0.4  A45  1.8  2.6  3.0 
 AMJ 2020  A60  76.3  0.4  A40  1.2  1.6  1.8 
 MJJ 2020  A55  78.2  0.4  A40  0.8  1.4  1.6 
 JJA 2020  A50  79.9  0.4   EC  0.7  0.8  1.3 
 JAS 2020  A45  81.3  0.4   EC  1.0  1.4  1.7 
 ASO 2020  A40  81.7  0.4   EC  1.6  2.4  3.1 
 SON 2020   EC  81.4  0.4   EC  2.5  4.0  5.6 
 OND 2020   EC  80.0  0.4   EC  4.4  6.4  8.5 
 NDJ 2020   EC  77.7  0.5   EC  3.9  5.6  8.8 
 DJF 2021   EC  75.3  0.5   EC  3.7  5.6  8.6 
 JFM 2021   EC  73.9  0.4   EC  2.1  4.6  7.8 
 FMA 2021   EC  73.8  0.4   EC  1.9  3.2  4.7 
 MAM 2021   EC  74.8  0.4   EC  1.8  2.6  3.0 
 

















 Lihue
  TEMPERATURE  PRECIPITATION
    FCST  AVE  LIM  FCST  BLW  MEDIAN  ABV
 MAM 2020  A65  72.8  0.5  A45  5.3  6.6  8.0 
 AMJ 2020  A60  74.2  0.5  A40  4.7  5.5  6.0 
 MJJ 2020  A55  76.0  0.5  A40  4.9  5.4  5.9 
 JJA 2020  A50  77.7  0.4   EC  4.4  5.3  6.9 
 JAS 2020  A45  79.0  0.3   EC  5.3  6.1  7.8 
 ASO 2020  A40  79.4  0.3   EC  6.2  7.9  8.4 
 SON 2020   EC  79.1  0.3   EC  9.2  10.0  11.2
 OND 2020   EC  77.8  0.3   EC  9.2  11.7  15.6
 NDJ 2020   EC  75.7  0.3   EC  8.6  12.1  16.9
 DJF 2021   EC  73.6  0.4   EC  7.5  8.4  14.0
 JFM 2021   EC  72.2  0.4   EC  6.5  8.8  13.8
 FMA 2021   EC  72.1  0.5   EC  5.8  8.4  9.9 
 MAM 2021   EC  72.8  0.5   EC  5.3  6.6  8.0 
 

FORECASTER: Dan Collins 
 
Anomalies are based on the 1981-2010 means. 
 
CLARIFICATION: EC indicated equal chances that the predicted parameter will fall into any one of the three categories, whose boundaries are specific in the tables above. A forecast specification of EC means there is no particulate tilt of the odds toward above normal or below normal conditions in the outlook. For example A40 means a 40% chance that the average temperature or total precipitation will be in the above normal class, B40 means a 40% chance that the average temperature or total precipitation will be in the below normal class, and N35 means a 35% probability that the average temperature or total 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 the valid periods. Within any valid period, observations and shorter range forecasts should be consulted. Also, this set of outlooks will be superseded by the issuances of the new set next month, on Thu Mar 19, 2020.
 
 
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