[Bazmundo]

Reports of damage from a land-falling tornado, with wind speeds estimated 60-70mph and exploded windows and shed damage.

http://www.hawaiinew...n-windward-oahu

[Bazmundo]

Also now confirmed as the largest hail size of any thunderstorm on Hawaii since 1950 - 4.25"

From RSOE:

Quote

A grapefruit-size hailstone that pummeled Oahu during a hailstorm this month has now been confirmed as the largest on record for the state of Hawaii, announced officials with the National Oceanic and Atmospheric Administration (NOAA). A final measurement of the hailstone, which dropped from the skies on March 9, places it at 4.25 inches long, 2.25 inches tall and 2 inches wide (10.8 by 5.7 by 5 centimeters). "According to hail report records for Hawaii kept back to 1950, the previous state record hailstone was 1 inch in diameter," Michael Cantin, warning coordination meteorologist at NOAA's National Weather Service (NWS) in Honolulu, said in a statement. The NWS, along with NOAA's State Climate Extremes Committee confirmed the new state record. The record-setting hailstone was dropped by a so-called supercell thunderstorm on the windward side of Oahu that also produced large hail in Kaneohe and Kailua. Perhaps the most violent of all thunderstorm types, supercell thunderstorms can generate damaging winds large hail, and even tornadoes, according to NOAA. They are most common during the spring across the central United States.

[Nigel Bolton]

Interesting.

From news reports looked like it occurred on 9th March. Does anyone have an archived synoptic chart to post???

News report gave tornado's direction as northwest - southeast. This suggests a synoptic pattern where cold air flowed southeastwards across progressively warmer seas to unusually southerly latitudes. The tornado was either spawned by a trough in this cold air, or perhaps by topography??? I have not yet looked at the relief of the local area, so cannot be sure just now.

Damage would suggest winds in excess of 70mph, perhaps to T2 strength, near 100 mph.

N.

[Bazmundo]

I can only find surface analysis for the wider Pacific, not localised to the islands. Attached 00z, 12z of the 9th and 00z of the 10th.

Attached thumbnail(s)

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[Nigel Bolton]

Thanks Bazmundo for charts.

Nailed it. Slow moving trough, easterly at the surface, southwesterly over the top. Ascent for Hilo shows stacks of Cape, and note the wind shear and veer. Classic.

http://weather.uwyo....0912&STNM=91285

N.