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<\/a>Hawai\u2018i radar image from earlier Saturday morning, May 16. (Courtesy Image: National Weather Service)<\/p>\nThe storm system brought with it very unstable air for the first time this year \u2014 enough to produce heavy showers or thunderstorms in some spots.<\/p>\n
Most were relatively brief, which made widespread flash flooding unlikely but kept a possibility of ponding water in poor drainage areas, and even some small hail, in the forecast during a few of the heavier downpours Friday and Friday night.<\/p>\n
Some of that heavy rainfall also reached the Big Island; however, the highest rain gauge totals on the island were below 4.5 inches compared with up to nearly 6 inches drenching a portion of Kaua\u2018i.<\/p>\n
Forecasters, in response to the increased threat of heavy rainfall, issued the flood watch, which was initially set to expire at 6 a.m. Saturday.<\/p>\n
ARTICLE CONTINUES BELOW ADARTICLE CONTINUES BELOW AD<\/p>\n
(For the period from 11:45 p.m. Thursday to Friday, May 14-15, recorded by automated rain gauges reporting to National Weather Service in Honolulu; totals are in inches.)<\/p>\n
Kaua\u2018i<\/p>\n
(all windward\/mauka sites)<\/p>\n
Mola\u02bba Dairy: 5.69<\/p>\n
L\u012bhu\u02bbe Airport: 4.58<\/p>\n
Anahola: 3.53<\/p>\n
Hanalei: 3.11<\/p>\n
Kapahi: 2.44<\/p>\n
Hawai\u2018i Island<\/p>\n
(all windward sites)<\/p>\n
Honoli\u02bbi Stream: 4.27<\/p>\n
Pi\u2018ihonua: 2.60<\/p>\n
Kula\u02bbimano: 1.87<\/p>\n
Institute of Pacific Islands Forestry: 1.62<\/p>\n
Mountain View: 1.62<\/p>\n
Laup\u0101hoehoe Power Development: 1.41<\/p>\n
Hilo Airport: 1.15<\/p>\n
Glenwood: 1.13<\/p>\n
Saddle Quarry: 1.04<\/p>\n
Spencer: 1.01<\/p>\n
Note: These are provisional totals that have not been quality controlled.<\/p>\n
The National Weather Service area forecast discussion for the state<\/a>, most recently issued just after 3:30 a.m. Saturday, reports that a slightly unstable trade wind flow will prevail today as the upper-level low weakens, producing isolated heavy showers and possibly thunderstorms mainly on the Big Island because of increased low-level moisture filtering in from the east.<\/p>\n ARTICLE CONTINUES BELOW AD<\/p>\n Moderate easterly trade winds, however, will focus rainfall over windward areas of all islands<\/p>\n Somewhat wet easterly trade winds will focus most rainfall along windward slopes Sunday, May 17, and into early next week before a more stable, moderate to breezy trade wind flow develops Tuesday and Wednesday, May 19-20.<\/p>\n Heavy showers and thunderstorms decreased dramatically Friday night as the storm system over the islands weakened.\u00a0Easterly trades focused mainly moderate showers over windward slopes overnight into Saturday.<\/p>\n There is some lingering instability from the passing storm, but so far, only a few heavy showers briefly flared up, even with a steady supply of low-level moisture streaming into windward Big Island.<\/p>\n Chance of heavy showers and thunderstorms will continue to diminish Saturday as the low pressure system drifts eastward and weakens.<\/p>\n ARTICLE CONTINUES BELOW AD<\/p>\n Moderate easterly winds and a somewhat wet pattern of mainly windward and mauka showers is expected Sunday into early Tuesday as the weakening storm system is eventually replaced with a broad and flat upper-level trough, which will not allow the atmosphere to become very stable.<\/p>\n Briefly heavy shower, mainly over heated leeward slopes of the Big Island and Maui during the afternoon cannot be ruled out as a result.<\/p>\n