National Weather Service United States Department of Commerce

Flash Flood Threats in Florida, New Mexico, and New England; Excessive Heat in the Southwest

Flash and small stream flooding threats linger across the southern Rockies today. Strong thunderstorms with heavy downpours may cause local flash flooding in Florida and New England. Excessive heat will continue to impact the southern California, Arizona and Nevada into Thursday. Read More >

 

PEAC Seasonal Rainfall Outlook

The PEAC Seasonal Rainfall Outlook is an experimental consenus forecast, produced monthly for 14 stations within Hawaii and the USAPI. The PEAC Outlook uses data from the following 7 models: UKMO, NASA GMAO, ECMWFIRINCEP Constructed AnalogNCEP Coupled Model and APCC MME.

The PEAC Seasonal Rainfall Outlook is a probabalistic forecast displayed in tercile form (3 categories). The three categories represent the chances of an event falling into the "Below Average", "Near Average" and "Above Average" categories, respectively. For example, a seasonal rainfall forecast of 20:30:50 should be interpreted as follows: There is a 20% chance of "Below Average" rainfall for the season; a 30% chance of "Near Average" rainfall for the season; and a 50% chance of "Above Average" rainfall for the season.

For more information on terciles, click here.

PEAC services is no longer providing the in house model, PEAC CCA as of January 2021. 

 


July-August-July (JAS) 2021

Model:
UKMO
ECMWF

NCEP CA

NASA GMAO
NCEP Coupled
IRI
APCC
PEAC CCA
Final Outlook
Final Probabilities
 
Republic of Palau
 

Airai

L 7 ° 22' N,
λ 134° 32' E
Avg-Above
Below
Avg-Below
Below
Avg-Above
Avg.
Avg.
-
Avg-Below
35:35:30
 
Federated States of Micronesia
 
Yap
L 9° 29' N,
λ 138° 05' E
Avg.
Below
Below
Avg-Below
Avg.
Avg-Below
Below
-
Avg-Below
35:35:30
Chuuk
L 7° 28' N,
λ 151° 51' E
Avg-Below
Below
Avg.
Avg.
Avg.
Avg-Below
Avg-Below
-
Avg-Below
35:35:30
Pohnpei
L 6 ° 59' N,
λ 158° 12' E
Avg-Below
Below
Avg.
Avg.
Avg.
Avg-Below
Avg.
-
Avg-Below
35:35:30
Kosrae
L 5 ° 21' N,
λ 162° 57' E
Avg.
Below
Avg-Above
Below
Avg.
Avg.
Avg.
-
Avg-Below
35:35:30
 
Republic of the Marshall Islands
 
Kwajalein
L 8 ° 43' N,
λ 167° 44' E
Below
Below
Avg.
Avg-Above
Avg.
Avg-Below
Avg-Below
-
Avg-Below
35:35:30
Majuro
L 7° 04' N,
λ 171° 17' E
Avg.
Avg-Below
Avg-Above
Avg.
Avg.
Avg-Below
Avg.
-
Avg.
30:40:30
 
Guam and CNMI
 
Guam
L 13 ° 29' N,
λ 144° 48' E
Below
Below
Below
Avg-below
Avg.
Avg.
Avg-below
-
Avg-Below
35:35:30
Saipan
L 15 ° 06' N,
λ 145° 48' E
Below
Below
Below
Avg-below
Avg.
Avg.
Avg-below
-
Avg-Below
35:35:30
 
American Samoa
 
Pago Pago
L 14 ° 20' S,
λ 170° 43' E
Clim.
Below
Avg.
Avg.
Avg.
Avg.
Avg-Below
-
Avg.
30:40:30
 
State of Hawaii
 
Lihue
L 21 ° 59' N,
λ 159 ° 20' E
Below
Below
Avg-Below
Avg-Below
Avg.
Below
Avg-Below
-
Below
40:35:25
Honolulu
L 21 ° 19' N,
λ 157° 56' W
Below
Below
Avg-Below
Avg-Below
Avg.
Below
Avg-Below
-
Below
40:35:25
Kahului
L 20 ° 54' N,
λ 156° 26' E
Below
Below
Avg-Below
Avg-Below
Avg.
Below
Avg-Below
-
Below
40:35:25
Hilo
L 19 ° 43' N,
λ 155° 03' E
Below
Below
Avg-Below
Avg-Below
Avg-Below
Below
Avg-Below
-
Below
40:35:25

 


Forecast Discussion

 

Airai: Rainfall for July-August-July 2021 is expected to be Avg-below for Airai. There is a 35% chance that rainfall during the JAS season will be less than 39.25 inches; a 35% chance that rainfall will be between 39.25 inches and 50.04 inches; and a 30% chance that rainfall will be greater than 55.04 inches.

Yap: Rainfall for July-August-July 2021 is expected to be Avg-below for Yap. There is a 35% chance that rainfall during the JAS season will be less than 41.9 inches; a 35% chance that rainfall will be between 41.9 inches and 46.11 inches; and a 30% chance that rainfall will be greater than 46.11 inches.

Chuuk: Rainfall for July-August-July 2021 is expected to be Avg-below for Chuuk. There is a 35% chance that rainfall during the JAS season will be less than 34.86 inches; a 35% chance that rainfall will be between 34.86 inches and 44.29 inches; and a 30% chance that rainfall will be greater than 44.29 inches.

Pohnpei: Rainfall for July-August-July 2021 is expected to be Avg-below for Pohnpei. There is a 35% chance that rainfall during the JAS season will be less than 40.06 inches; a 35% chance that rainfall will be between 40.06 inches and 50.76 inches; and a 30% chance that rainfall will be greater than 50.76 inches.

Kosrae: Rainfall for July-August-July 2021 is expected to be Avg-below for Kosrae. There is a 35% chance that rainfall during the JAS season will be less than 41.49 inches; a 35% chance that rainfall will be between 41.49 inches and 47.32 inches; and a 30% chance that rainfall will be greater than 47.32  inches.

Kwajalein: Rainfall for July-August-July 2021 is expected to be Avg-below for Kwajalein. There is a 35% chance that rainfall during the JAS season will be less than 28.97 inches; a 35% chance that rainfall will be between 28.97 inches and 33.09 inches; and a 30% chance that rainfall will be greater than 33.09 inches.

Majuro: Rainfall for July-August-July 2021 is expected to be  for Average Majuro. There is a 35% chance that rainfall during the JAS season will be less than 31.17 inches; a 35% chance that rainfall will be between 31.17 inches and 38.16 inches; and a 30% chance that rainfall will be greater than 38.16 inches.

Guam: Rainfall for July-August-July 2021 is expected to be Avg-below for Guam. There is a 35% chance that rainfall during the JAS season will be less than 37.2 inches; a 35% chance that rainfall will be between 37.2 inches and 44.54 inches; and a 30% chance that rainfall will be greater than 44.54 inches.

Saipan: Rainfall for July-August-July 2021 is expected to be Avg-below for Saipan. There is a 35% chance that rainfall during the JAS season will be less than 29.48 inches; a 35% chance that rainfall will be between 29.48 inches and 35.85 inches; and a 30% chance that rainfall will be greater than 35.85 inches.

Pago Pago: Rainfall for July-August-July 2021 is expected to be Avg. for Pago Pago. There is a 30% chance that rainfall during the JAS season will be less than 15.04 inches; a 40% chance that rainfall will be between 15.04 inches and 23.4 inches; and a 30% chance that rainfall will be greater than 23.4 inches.

Lihue: Rainfall for July-August-July 2021 is expected to be Below  for Lihue. There is a 40% chance that rainfall during the JAS season will be less than 5.27 inches; a 35% chance that rainfall will be between 5.27 inches and 7.79 inches; and a 25% chance that rainfall will be greater than 7.79 inches.

Honolulu: Rainfall for July-August-July 2021 is expected to be Below for Honolulu. There is a 40% chance that rainfall during the JAS season will be less than 1.02 inches; a 35% chance that rainfall will be between 1.02 inches and 1.67 inches; and a 25% chance that rainfall will be greater than 1.67 inches.

Kahului: Rainfall for July-August-July 2021 is expected to be Below for Kahului. There is a 40% chance that rainfall during the JAS season will be less than 0.84 inches; a 35% chance that rainfall will be between 0.84 inches and 1.64 inches; and a 25% chance that rainfall will be greater than 1.64 inches.

Hilo: Rainfall for July-August-July 2021 is expected to be Below for Hilo. There is a 40% chance that rainfall during the JAS season will be less than 25.17 inches; a 35% chance that rainfall will be between 25.17 inches and  33.44 inches; and a 25% chance that rainfall will be greater than 33.44 inches.


The PEAC Seasonal Rainfall Outlook is an experimental consensus forecast, produced monthly by the Pacific ENSO Applications Climate (PEAC) Service's for 14 stations within Hawaii and the USAPI. Tercile cut-offs for each location and season are based on Pacific Rainfall Climatologies (Climate Prediction Center) 1981-2010. The new climatologies are currently in the works and will be integrated once approved. Last Updated: July 10, 2021