Hawaii 30 & 90 Day Narrative

459 
FXHW40 KWBC 211231
PMDHCO
Prognostic Discussion for Long-Lead Hawaiian Outlooks
NWS Climate Prediction Center College Park MD
830AM EST Thu Mar 21 2019
MONTHLY FORECAST DISCUSSION VALID APRIL 2019
Sea surface temperature (SST) anomalies were around negative one-half degree C 
to negative one degree C near the Hawaiian Islands during the last week.
For February 2019, rainfall total accumulations were:
- Lihue Airport 3.53 inches (51 percent of normal)
- Honolulu Airport 2.50 inches (58 percent of normal)
- Kahului Airport 7.71 Inches (162 percent of normal)
- Hilo Airport 12.50 Inches (66 percent of normal)
Although the NCEP Climate Forecast System (CFS) and other climate models of the 
North American Multi-Model Ensemble (NMME) predict near to above normal SSTs 
around the Hawaiian Islands for April 2019, recent SST anomaly observations 
show a cooling trend. Hence Equal Chances (EC) for above, near, or below normal 
temperatures are indicated for the Hawaiian Islands for April 2019. Most 
dynamical models predict below normal precipitation over the Hawaiian Islands 
during April 2019, which is also consistent with the low-frequency state over 
the tropical Pacific.
           TEMPERATURE           PRECIPITATION
          FCST   AVE    LIM  FCST  BLW  MEDIAN  ABV
Hilo        EC   72.6   0.7  B60   7.4   8.9   11.2
Kahului     EC   74.1   0.6  B60   0.5   0.9   1.3
Honolulu    EC   76.3   0.5  B60   0.3   0.5   0.7
Lihue       EC   74.0   0.6  B60   1.6   1.9   2.8
SEASONAL FORECAST DISCUSSION VALID AMJ 2019 - AMJ 2020
Refer to the prognostic discussion on 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. Weak EL Nino conditions currently are present across the 
equatorial Pacific Ocean. Equatorial sea surface temperatures (SSTs) are above 
average across most of the equatorial Pacific Ocean. Positive subsurface 
temperature anomalies have persisted across most of the equatorial Pacific 
Ocean, while negative subsurface temperature anomalies have appeared between 
100W and 90W. Convection was enhanced near the Date Line, while low-level wind 
anomalies were westerly across the western Pacific Ocean, and upper-level winds 
were anomalous westerly over the western and far eastern Pacific. Most models 
indicate weak El Nino conditions are likely to continue through the Northern 
Hemisphere spring 2019 (about 80% chance) and summer (about 60% chance).
Enhanced probabilities for above normal temperatures are indicated for Hawaii 
from AMJ to ASO 2019 due to predicted above normal sea surface temperatures 
across the region according to statistical and dynamical models. Equal chances 
(EC) for above, near, or below normal temperatures are indicated for all of the 
Hawaiian Islands for SON 2019 and beyond, due to increasing uncertainty in 
climate conditions at longer lead times.
With the predicted continuation of an El Nino, the precipitation forecast for 
Hawaii follows historical El Nino impacts that indicate strong correlations 
between El Nino and increased probabilities of below normal precipitation in 
winter and spring. The precipitation outlook is consistent with NMME dynamical 
model forecasts and statistical tools, including Constructed Analog, Canonical 
Correlation Analysis, and an ENSO-OCN tool (that combines the impacts of El 
Nino and decadal climate variability), indicating below normal precipitation 
for Hilo and Kahului from AMJ to MJJ 2019 and for Honolulu and Lihue from AMJ 
to JJA 2019. There is considerable uncertainty across the Hawaiian Islands in 
the precipitation forecast among available forecast tools in JAS 2019 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
AMJ 2019  A40  72.9   0.5   B50   21.4   23.7   29.0
MJJ 2019  A45  74.0   0.4   B40   20.2   27.5   29.1
JJA 2019  A55  75.2   0.4    EC   19.4   27.2   31.4
JAS 2019  A45  76.1   0.4    EC   25.2   28.6   33.4
ASO 2019  A40  76.4   0.4    EC   26.1   28.8   33.3
SON 2019   EC  76.2   0.4    EC   24.3   30.2   40.8
OND 2019   EC  75.5   0.4    EC   28.3   34.5   42.0
NDJ 2019   EC  74.2   0.4    EC   26.4   36.6   43.0
DJF 2020   EC  72.8   0.4    EC   19.6   30.2   33.3
JFM 2020   EC  71.8   0.4    EC   22.0   32.0   44.5
FMA 2020   EC  71.7   0.4    EC   24.6   34.1   45.5
MAM 2020   EC  72.0   0.5    EC   22.5   28.4   34.0
AMJ 2020   EC  72.9   0.5    EC   21.4   23.7   29.0
                      Kahului
          TEMPERATURE           PRECIPITATION
         FCST   AVE   LIM  FCST   BLW  MEDIAN   ABV
AMJ 2019  A40  74.3   0.5   B50   1.2    1.6    2.2 
MJJ 2019  A45  76.0   0.5   B40   0.7    1.1    1.8 
JJA 2019  A55  77.7   0.4    EC   0.7    1.1    1.5 
JAS 2019  A45  79.0   0.4    EC   0.8    1.1    1.6 
ASO 2019  A40  79.4   0.4    EC   0.8    1.6    2.5 
SON 2019   EC  79.1   0.4    EC   2.1    3.3    4.8 
OND 2019   EC  77.8   0.4    EC   4.2    5.3    8.1 
NDJ 2019   EC  75.9   0.4    EC   5.2    7.6    9.5 
DJF 2020   EC  73.8   0.4    EC   4.6    6.9    8.7 
JFM 2020   EC  72.5   0.4    EC   4.2    6.2    8.2 
FMA 2020   EC  72.3   0.4    EC   3.2    4.1    6.4 
MAM 2020   EC  73.0   0.4    EC   2.5    3.5    4.6 
AMJ 2020   EC  74.3   0.5    EC   1.2    1.6    2.2 
                      Honolulu
          TEMPERATURE           PRECIPITATION
         FCST   AVE   LIM  FCST   BLW  MEDIAN   ABV
AMJ 2019  A40  76.3   0.4   B50   1.2    1.6    1.8 
MJJ 2019  A45  78.2   0.4   B45   0.8    1.4    1.6 
JJA 2019  A55  79.9   0.4   B40   0.7    0.8    1.3 
JAS 2019  A45  81.3   0.4    EC   1.0    1.4    1.7 
ASO 2019  A40  81.7   0.4    EC   1.6    2.4    3.1 
SON 2019   EC  81.4   0.4    EC   2.5    4.0    5.6 
OND 2019   EC  80.0   0.4    EC   4.4    6.4    8.5 
NDJ 2019   EC  77.7   0.5    EC   3.9    5.6    8.8 
DJF 2020   EC  75.3   0.5    EC   3.7    5.6    8.6 
JFM 2020   EC  73.9   0.4    EC   2.1    4.6    7.8 
FMA 2020   EC  73.8   0.4    EC   1.9    3.2    4.7 
MAM 2020   EC  74.8   0.4    EC   1.8    2.6    3.0 
AMJ 2020   EC  76.3   0.4    EC   1.2    1.6    1.8 
                      Lihue
          TEMPERATURE           PRECIPITATION
         FCST   AVE   LIM  FCST   BLW  MEDIAN   ABV
AMJ 2019  A40  74.2   0.5   B50   4.7    5.5    6.0 
MJJ 2019  A45  76.0   0.5   B45   4.9    5.4    5.9 
JJA 2019  A55  77.7   0.4   B40   4.4    5.3    6.9 
JAS 2019  A45  79.0   0.3    EC   5.3    6.1    7.8 
ASO 2019  A40  79.4   0.3    EC   6.2    7.9    8.4 
SON 2019   EC  79.1   0.3    EC   9.2    10.0   11.2
OND 2019   EC  77.8   0.3    EC   9.2    11.7   15.6
NDJ 2019   EC  75.7   0.3    EC   8.6    12.1   16.9
DJF 2020   EC  73.6   0.4    EC   7.5    8.4    14.0
JFM 2020   EC  72.2   0.4    EC   6.5    8.8    13.8
FMA 2020   EC  72.1   0.5    EC   5.8    8.4    9.9 
MAM 2020   EC  72.8   0.5    EC   5.3    6.6    8.0 
AMJ 2020   EC  74.2   0.5    EC   4.7    5.5    6.0 
FORECASTER: Luke He
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 net month, on Thu Apr 18, 2019.
$$