Hawaii County climate forecast is September 11, 2021

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Photo credit: James Grenz

Hilo

Today: Mostly cloudy. Numerous showers in the morning, then isolated showers in the afternoon. Heights from 77 to 83 near the shore to 64 to 70 at 4000 feet. East wind up to 10 km / h. Chance of rain 70 percent.

Tonight: cloudy. Numerous showers in the evening, then showers after midnight. Lows of 64 to 72 near shore at 54 to 59 at 4000 feet. West winds up to 10 km / h. Chance of rain 90 percent.

Sunday: Mostly cloudy. Numerous showers in the morning, then isolated showers in the afternoon. Heights from 77 to 83 near shore to 63 to 70 at 4000 feet. Northeast winds up to 15 miles per hour. Chance of rain 70 percent.

Kona

Today: Mostly sunny in the morning, then mostly cloudy with a few showers in the afternoon. Heights from 83 to 88 near shore to about 67 near 5000 feet. In the afternoon the northwest wind blows at up to 16 km / h on the southwest. 50 percent chance of rain.

Tonight: Mostly cloudy with a few showers in the evening, then partly cloudy with a few showers after midnight. Lows of 70 to 75 near shore to about 54 near 5000 feet. Breeze. 50 percent chance of rain.

THE ARTICLE CONTINUES BELOW THE ADVERT

Sunday: Mostly sunny in the morning, then mostly cloudy with a few showers in the afternoon. Highs from 81 to 86 near shore to about 67 near 5000 feet. Breeze. 50 percent chance of rain.

Waimea

THE ARTICLE CONTINUES BELOW THE ADVERT

Today: Partly sunny with a few showers. Maximum values ​​64 to 84. East winds up to 24 km / h. 50 percent chance of rain.

Tonight: Mostly cloudy with a few showers. Lows of 63 to 70 near shore to 56 to 63 near 3000 feet. East winds 10 to 15 miles per hour. 50 percent chance of rain.

Sunday: windy. Partly sunny with a few showers. Highs 63 to 83. East winds 10 to 20 miles per hour. 50 percent chance of rain.

Kohala

THE ARTICLE CONTINUES BELOW THE ADVERT

Today: Partly sunny with a few showers. Maximum values ​​64 to 84. East winds up to 24 km / h. 50 percent chance of rain.

Tonight: Mostly cloudy with a few showers. Lows of 63 to 70 near shore to 56 to 63 near 3000 feet. East winds 10 to 15 miles per hour. 50 percent chance of rain.

Sunday: windy. Partly sunny with a few showers. Highs 63 to 83. East winds 10 to 20 miles per hour. 50 percent chance of rain.

Southern big island

Today: Mostly sunny in the morning, then mostly cloudy with a few showers in the afternoon. Altitudes around 83 near shore to about 65 near 5000 feet. East wind up to 15 km / h. Chance of rain 20 percent.

Tonight: In the evening mostly cloudy with a few showers, then mostly clear after midnight. Lows of 73 near shore to about 53 near 5000 feet. Northeast winds up to 15 miles per hour. Chance of rain 20 percent.

Sunday: windy. Sunny mornings, mostly cloudy with a few showers in the afternoon. Altitudes around 83 near shore to 66 near 5000 feet. East wind up to 20 km / h. Chance of rain 20 percent.

feedback

Today: Mostly cloudy. Numerous showers in the morning, then isolated showers in the afternoon. Heights from 77 to 83 near the shore to 64 to 70 at 4000 feet. East wind up to 10 km / h. Chance of rain 70 percent.

Tonight: cloudy. Numerous showers in the evening, then showers after midnight. Lows of 64 to 72 near shore at 54 to 59 at 4000 feet. West winds up to 10 km / h. Chance of rain 90 percent.

Sunday: Mostly cloudy. Numerous showers in the morning, then isolated showers in the afternoon. Heights from 77 to 83 near shore to 63 to 70 at 4000 feet. Northeast winds up to 15 miles per hour. Chance of rain 70 percent.

Waikoloa

Today: Mostly sunny. Heights from 83 to 89 near shore to 66 to 72 over 4000 feet. Northwest winds up to 10 km / h.

Tonight: Partly cloudy. Lows of 74 near shore to 51 to 56 over 4000 feet. Southeast winds up to 10 km / h.

Sunday: Mostly sunny. Heights from 83 to 88 near shore to 65 to 72 over 4000 feet. Northeast winds up to 15 miles per hour.

summary

A weakened high pressure ridge north of the area and an altitude low about 1000 miles northeast of the islands will continue to keep the trade winds in the light to moderate range today. The trade winds will increase in the moderate to breezy range on Sunday and Monday as the ridge becomes stronger. This unstable upper low will slowly drift west and weaken early next week, passing north of the Hawaiian Islands on Wednesday. Periods of heavy rain showers are likely on all islands through Friday as this unstable system slowly flows through the region.

discussion

GOES ‘water vapor satellite imagery this morning shows a narrow upper plain north of the state with an unstable upper low about 1000 miles northeast of the islands. A subtropical jet stream just south of the upper trough will continue to create periods of high cirrus clouds that enhance the colors from sunrise and sunset through Sunday. The infrared satellite images show moderately unstable cumulus clouds driven by the trade winds. A surface valley northeast of the islands, a reflection of the upper lows, will help weaken trade wind speeds across the region. This surface trough tends to weaken as the low slowly drifts west. Local radar images show isolated showers that break in on the trade winds.
The high pressure ridge north of the state is split by a cold front moving through the Eastern Pacific. The upper level deep in the northeast of the islands continues to produce a surface ridge northeast of the islands. Both trough features will reduce the strength of the trade winds today. Expect another day of light to moderate trade winds throughout the region with weak sea breezes during the day limited to protected areas along the western slopes of each island. An increase in the trade winds in the moderate to locally airy range is forecast for Sunday and Monday. The trade wind speeds will decrease again from Tuesday to the light to medium range, as the upper low just north of the island chain slowly passes by.
On the precipitation side, increased showers are expected for all islands during the week as this upper low slowly passes north of the state. Model cross-sections show trade wind inversion heights around the 8,000-foot level creating lower cloud heights and more shower cover. Rain activity will increase in all areas, with the highest amounts of rainfall favoring the typical windward and mountainous areas. In the lee areas, however, there will also be periods with increased precipitation coverage until next Friday. On Wednesday and Thursday, deeper moisture will be drawn in from the south, resulting in higher rain coverage as the upper lower center passes north of the state. The amount of precipitation was increased in the morning forecast grids for this period.

aviation

High pressures in the north of the state will keep light to moderate trade winds in place until tonight. Clouds and showers favor slopes and coasts on the windward side, with an occasional shower pouring into the leeward communities from time to time. Short MVFR cigs / vsbys are possible with passing showers, mainly along the windward slopes and coastlines. Otherwise, VFR conditions will prevail for the next 24 hours.
AIRMET Sierra remains in effect to darken mountains on windward portions of Kauai. This morning the conditions should improve here.

marine

The weak surface trough in the northeastern state, which has resulted in light to moderate trades recently, is being washed out this morning. The pressure gradient of high pressure in the northeast of the state will become more dominant and will produce a healthy regime of moderate to fresh trade winds late through Monday today. The only chance for winds hitting the Small Craft Advisory thresholds this weekend is early Sunday over the canals and bays of the East Island, particularly the Alenuihaha Channel. A small change in the regional large-scale pressure gradient corresponds to a generally solid, moderate north-east-east trading up to the middle of the month.
A series of overlapping small, long-lasting south-southeast swells will hold slightly below average surf along the south-facing banks for the next few days. A slightly larger swell with longer energy crosses the Samoa buoy this morning. This swell should reach the islands sometime on Monday and bring the south surf back to almost seasonal heights on Tuesday and Wednesday. Recent observations have confirmed that more southern exposures along the western shorelines benefit from some of this southern swell that winds westward. Small wind wave swell from slightly stronger trades will cause choppy surf on many east walls this weekend. A small, medium-term northwest swell arriving on Sunday can bring the surf to just over flat for north coasts by early next week.

HFO watches / warnings / notices

None.

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Data courtesy of NOAA.gov

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