Temperatures this week in Alaska were generally 5-10 degrees below normal in the far north, near normal along the southern coast, 2-6 degrees below normal in central Alaska, and variable in southeast Alaska. Heavy precipitation in central and southwest Alaska led to the removal of short-term abnormal dryness, while rainfall surpluses and deficits and shifts in fire danger led to a small southward shift in short-term moderate drought on the Yukon Flats.

Mounting precipitation deficits and deteriorating crops and pastures led to an expansion of extreme drought and an introduction of exceptional drought in the Central Valley of Maui. On the Big Island, extreme drought in the northwest expanded as a result of mounting precipitation deficits.

The Inter-Tropical Convergence Zone (ITCZ) and trade-wind troughs spread rain across the middle third of Micronesia during this USDM week (July 27-August 2). A tropical disturbance, trade-wind troughs, and a Tropical Upper-Tropospheric Trough (TUTT) alternated during the week to bring abundant rain to the Marianas and other portions of western Micronesia. High pressure and stable air dominated American Samoa for much of the week, but showers embedded in the easterly trade-wind flow were common at times.

Several inches of rain fell across the Marianas this week, with Guam reporting 4.25 inches, Rota 5.40 inches, and Saipan IAP 6.30 inches. In the Republic of Palau, over 6 inches was recorded at the Koror COOP station. Two inches or more of rain fell across a middle stretch of the Federated States of Micronesia (FSM) and the Marshall Islands, while southern portions had a dry (less than 2 inches) week. It was a dry week in American Samoa, where Pago Pago recorded only 0.65 inch and about an inch (0.98) fell at the automated stations at Siufaga Ridge and Toa Ridge. But the month of July was wet across most of the U.S.-Affiliated Pacific Islands, with most locations reporting more than the 4-inch or 8-inch monthly minimum needed to meet most water needs. Only Fananu reported less than the 8-inch minimum (4.46 inches was reported), and this may be due to some missing data. Other than Lukunor, Kapingamarangi, and Nukuoro, those stations that had less than the 1- or 2-inch weekly minimum this week were wet (above the weekly min) last week and previous weeks.

Lukunor and Nukuoro have been dry (less than the weekly min) for the last 2 weeks, but previous weeks were wet and the July totals were well above the monthly minimum, so D-Nothing (no drought or abnormal dryness) continued for these locations. D-Nothing continued for the rest of the analyzed locations except Utirik (which had no data and was plotted as missing) and Kapingamarangi.

Fananu reported 4.93 inches of rain in the last two weeks but only 4.46 inches for the month of July (which is below the 8-inch monthly minimum needed to meet most water needs). With 2.20 inches of that 4.93 inches falling on August 1-2, Fananu was analyzed as D-Nothing.

Kapingamarangi had 8.60 inches for July, which is above the 8-inch monthly minimum, but the last 2 weeks have been dry (below the 2-inch weekly minimum) (0.88 inch last week and 0.57 inch this week). July 2022 ranks as the 10th driest July in 33 years of data, but June-July ranks 4th driest; May-July, April-July, and March-July rank driest on record; and the rest of the time periods from February-July (last 6 months) to August-July (last 12 months) rank 2nd or 3rd driest. The July 22 Drought Information Statement from the National Weather Service noted impacts continuing: Public and private water tanks are not replenished but above 50%, and vegetation is still yellow. With the last 2 weeks dry, percentiles for all time scales from the last 2 to 6 months (S) and 7 to 12 months (L) dry, and impacts continuing, the status at Kapingamarangi was changed from D1-L to D1-SL.

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