A dangerous and widespread summer heat wave is expected through this upcoming weekend across much of the Central and Eastern U.S. A large dome of high pressure will allow high temperatures to surge into the 90s and 100s in many locations, while heat indices will top 100 and approach 110 degrees or higher. There also will be no relief at night, as low temperatures remain in the upper 70s and 80s. Read More >
PEAC Seasonal Rainfall OutlookThe PEAC Seasonal Rainfall Outlook is an expirimental 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, ECMWF, IRI, NCEP Constructed Analog, NCEP 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.


July  August  September (JAS) 2019 





Forecast Discussion 

Koror: Rainfall for July August September 2019 is expected to be Average for Koror. There is a 30% chance that rainfall during the JAS season will be less than 54.17 inches; a 40% chance that rainfall will be between 54.17 inches and 63.33 inches; and a 30% chance that rainfall will be greater than 63.33 inches. Yap: Rainfall for July August September 2019 is expected to be Average for Yap. There is a 30% chance that rainfall during the JAS season will be less than 40.34 inches; a 40% chance that rainfall will be between 40.34 inches and 45.79 inches; and a 30% chance that rainfall will be greater than 45.79 inches. Chuuk: Rainfall for July August September 2019 is expected to be Average for Chuuk. There is a 30% chance that rainfall during the JAS season will be less than 33.35 inches; a 40% chance that rainfall will be between 33.35 inches and 43.35 inches; and a 30% chance that rainfall will be greater than 43.35 inches. Pohnpei: Rainfall for July August September 2019 is expected to be Average for Pohnpei. There is a 30% chance that rainfall during the JAS season will be less than 40.21 inches; a 40% chance that rainfall will be between 40.21 inches and 50 inches; and a 30% chance that rainfall will be greater than 50 inches. Kosrae: Rainfall for July August September 2019 is expected to be Average for Kosrae. There is a 30% chance that rainfall during the JAS season will be less than 43.42 inches; a 40% chance that rainfall will be between 43.42 inches and 46.35 inches; and a 30% chance that rainfall will be greater than 43.35 inches. Kwajalein: Rainfall for July August September 2019 is expected to be Average Below for Kwajalein. There is a 35% chance that rainfall during the JAS season will be less than 24.49 inches; a 35% chance that rainfall will be between 24.49 inches and 28.47 inches; and a 30% chance that rainfall will be greater than 28.47 inches. Majuro: Rainfall for July August September 2019 is expected to be for Average Below Majuro.There is a 35% chance that rainfall during the JAS season will be less than 31.08 inches; a 35% chance that rainfall will be between 31.08 inches and 35.58 inches; and a 30% chance that rainfall will be greater than 35.58 inches. Guam: Rainfall for July August September 2019 is expected to be Average for Guam. There is a 30% chance that rainfall during the JAS season will be less than 29.26 inches; a 40% chance that rainfall will be between 29.26 inches and 36.54 inches; and a 30% chance that rainfall will be greater than 36.54 inches. Saipan: Rainfall for July August September 2019 is expected to be Average for Saipan. There is a 30% chance that rainfall during the JAS season will be less than 21.38 inches; a 40% chance that rainfall will be between 21.38 inches and 30.82 inches; and a 30% chance that rainfall will be greater than 30.82 inches. Pago Pago: Rainfall for July August September 2019 is expected to be Above for Pago Pago. There is a 25% chance that rainfall during the JAS season will be less than 14.32 inches; a 35% chance that rainfall will be between 14.32 inches and 21.74 inches; and a 40% chance that rainfall will be greater than 21.74 inches. Lihue: Rainfall for July August September 2019 is expected to be Above for Lihue. There is a 25% chance that rainfall during the JAS season will be less than 4.39 inches; a 30% chance that rainfall will be between 4.39 inches and 6.88 inches; and a 45% chance that rainfall will be greater than 6.88 inches. Honolulu: Rainfall for July August September 2019 is expected to be Above for Honolulu. There is a 25% chance that rainfall during the JAS season will be less than 0.71 inches; a 30% chance that rainfall will be between 0.71 inches and 1.3 inches; and a 45% chance that rainfall will be greater than 1.3 inches. Kahului: Rainfall for July August September 2019 is expected to be Above for Kahului. There is a 25% chance that rainfall during the JAS season will be less than 0.74 inches; a 30% chance that rainfall will be between 0.74 inches and 1.51 inches; and a 45% chance that rainfall will be greater than 1.51 inches. Hilo: Rainfall for July August September 2019 is expected to be Above for Hilo. There is a 20% chance that rainfall during the JAS season will be less than 19.45 inches; a 30% chance that rainfall will be between 19.45 inches and 31.4 inches; and a 50% chance that rainfall will be greater than 31.4 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 cutoffs for each location and season are based on Pacific Rainfall Climatologies (Climate Prediction Center) 19812010. The PEAC Seasonal Rainfall Outlook for July August September (JAS) 2019 was made available on 12 July 2019. 