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Drought Information Statement  Issued: 09/09/2020 10:55:50 AM HST


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Drought Information Statement
National Weather Service Honolulu HI
1055 AM HST Wed Sep 9 2020

...DROUGHT WORSENS ACROSS THE MAIN HAWAIIAN ISLANDS...

.SYNOPSIS:
Dry conditions during August reversed improvements in drought that
occurred during July. The worst drought conditions were in Maui
County, where severe drought, or the D2 category in the U.S.
Drought Monitor map, covered portions of Maui, Molokai, Lanai, and
Kahoolawe. These conditions are not expected to improve in the
near term and may soon transition to extreme drought, or the D3 category.

On the Big Island, below normal trade wind rainfall resulted in
moderate drought, or the D1 category, spreading into the windward
slopes from Laupahoehoe to Kilauea volcano. Moderate drought also
covered most of the Big Island`s South Kohala District and the
leeward portions of the North Kohala District.

Elsewhere in the state, moderate drought on Oahu increased in
coverage during the past month and now covers the southwestern
half of the island. Kauai has been the least impacted by drought
this summer but over the past month has trended toward the return
of moderate drought over the leeward side of the island.

.SUMMARY OF IMPACTS:
Kauai County
Ground observations indicated that pastures and general
vegetation are drying along the leeward slopes, especially near
Hanapepe.

Oahu (City and County of Honolulu)
Dry conditions during August have caused the deterioration of vegetation
across the leeward areas of the island. Satellite-based vegetation
health data indicated deteriorating conditions in the central and
western portions of the island. There have not yet been reports of
agriculture impacts, and most of the public water supply is from more
resilient ground sources.

Maui County
The Farm Service Agency indicated that numerous producers were reporting
dry pasture conditions, especially along the leeward slopes of Haleakala.
Ground observations from Molokai validated the poor vegetation health
detected by satellite over the western half of the island. Similarly,
a report from Lanai indicated worsening vegetation conditions, especially
over the southern half of the island.

Hawaii County
Conditions were very dry in many areas of the Big Island,
especially during the latter half of August. The exception is the Kona
slopes region, which received ample rainfall during the summer.
The low surface water flow levels have impacted a sturgeon farm in
the Hilo area and the producer has had to provide supplemental
aeration. The Farm Service Agency reported that numerous producers
have indicated dry pasture conditions. The Natural Resources
Conservation Service reported that grasses in the Waikii and Mana
areas were showing signs of drought stress. Satellite-based
vegetation health data also indicated degraded conditions over the
eastern slopes of Mauna Kea along the Mana Road from Keanakolu to
the Humuula Saddle, and the lower slopes of the Kau District from
Pahala to South Point.

.DROUGHT MITIGATION ACTIONS:
The U.S. Department of Agriculture declared Hawaii County and Maui
County as Primary Natural Disaster Areas in March 2020. The
declaration allows the Farm Service Agency to extend emergency
credit to producers affected by drought conditions during recent
months.

The Maui County Department of Water Supply declared a Stage 1 Water
Shortage for Upcountry and West Maui on September 1. Reservoir levels
have steadily dropped over the past month. The declaration requests
residents in the affected areas to cut back on non-essential water
use until further notice.

.LOCAL DROUGHT OUTLOOK:
The Long-Lead Hawaiian Islands Outlook issued on August 20 by the
NOAA Climate Prediction Center shows probabilities favoring below
normal rainfall during the early fall of 2020. Rainfall should
continue to favor the east-facing windward slopes, with leeward
areas becoming drier. The outlook projects a transition to above
normal rainfall in late 2020. Probabilities continue to favor
above normal temperatures across the state through the rest of
2020 and into early 2021 due to the forecast of above average sea
surface temperatures around the Hawaiian Islands. The next long-
lead outlook will be issued by the Climate Prediction Center on
September 17.

Based on the forecast, and barring any tropical cyclone near passes
or direct hits, leeward dryness will likely persist, resulting in
a potential worsening and expansion of current drought areas across
the state into early fall before easing late in 2020.

.NEXT ISSUANCE DATE:
The next Drought Information Statement will be issued on October
8, 2020 or sooner if necessary in response to significant changes
in conditions.

.RELATED WEB SITES:
Additional information on current drought conditions may be found
at the following web addresses:

U.S. Drought Monitor:
droughtmonitor.unl.edu/

Hawaii Drought Monitor:
dlnr.hawaii.gov/drought

USGS Hawaii - Recent Conditions:
hi.water.usgs.gov/recent/index.html

Climate Prediction Center long-lead Hawaii outlook:
www.cpc.ncep.noaa.gov/products/predictions/90day/fxhw40.html

Hawaii Drought Impact Reporter:
hawaii.droughtreporter.unl.edu/

.ACKNOWLEDGMENTS:
Information for this product was compiled from a number of sources
including the county boards and departments of water supply, U.S.
and State of Hawaii agriculture agencies, the U.S. Geological Survey,
and the media.

.CONTACT INFORMATION:
If you have questions or comments about this drought information
statement, please contact:

Kevin Kodama
National Weather Service
2525 Correa Rd. Suite 250
Honolulu HI 96822
Phone: 808-973-5276
Email: Kevin.kodama@noaa.gov

$$