Hawaii: severe thunderstorm watch#1 issued and warnings too

[spinfan4eva]

Unusual
http://www.prh.noaa.gov/pr/hnl/

WATCH COUNTY NOTIFICATION FOR WATCH 1
NATIONAL WEATHER SERVICE HONOLULU HI
333 PM HST TUE FEB 21 2006

HIC003-007-220600-
/O.EXT.PHFO.SV.A.0001.000000T0000Z-060222T0600Z/

SEVERE THUNDERSTORM WATCH 1...PREVIOUSLY IN EFFECT UNTIL 8 PM HST
WEDNESDAY...IS NOW IN EFFECT UNTIL 8 PM HST THIS EVENING FOR THE
FOLLOWING AREAS

IN HAWAII THIS WATCH INCLUDES 2 COUNTIES

HONOLULU
KAUAI

THIS INCLUDES THE CITIES OF...HONOLULU AND LIHUE

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE HONOLULU HI
509 PM HST TUE FEB 21 2006

THE NATIONAL WEATHER SERVICE IN HONOLULU HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
THE ISLAND OF OAHU IN HONOLULU COUNTY

* UNTIL 545 PM HST

* AT 504 PM HST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS
OF 60 MPH. THIS STORM WAS LOCATED JUST WEST OF KAENA POINT...OR
ABOUT 34 MILES NORTHWEST OF HONOLULU...AND MOVING NORTHEAST AT 15
MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
MOKULEIA BY 530 PM HST
WAIALUA AND HALEIWA BY 545 PM HST

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...DESTRUCTIVE HAIL...AND DEADLY CLOUD
TO GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

[Aslkahuna]

Not all that unusual-the storms are moving NE which means a mean layer Southerly to Southwesterly flow called a Kona in the islands. This flow is opposite to the far more persistent and common Trades so the normally leeward sides of the Islands are now windward. Konas are usually associated with closed cold core ULLs W-NW of the Islands where the cold air aloft destabilizes the air and the jet streaks rotating around the Low provide the dynamics for strong to severe thunderstorms. Kona Lows can dump some quite copious quantities of rain upon the Islands and since the moisture is deeper, the very strong orographic effects of the Trades are muted-it's during these patterns with the cold air aloft that Mauna Loa and Mauna Kea get their winter snow.

Steve