Hail in Oregon, August 7, 2013

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
216 PM PDT WED AUG 7 2013

.DISCUSSION...THE UPPER LOW CONTINUES TO SPIN OFFSHORE AND BRINGING
IN MULTIPLE SHORTWAVES OVER THE FORECAST AREA. CURRENT IR IMAGE
SHOWS THE BIGGEST CHUNK OF CONVECTION OVER THE MARINE WATERS. THREE
OTHER AREAS OF CONCERN ARE A LINE OF CLOUDS ORIENTED FROM SOUTHEAST
TO NORTHWEST AND THE IR IMAGE HAS SHOWN SOME CLOUD TOP COOLING
SECOND ARE CUMULUS BUILD UPS WHERE THE SKIES ARE MOSTLY CLEAR IN
SOUTHWEST OREGON AND MOST OF SISKIYOU COUNTY WITH THE BLOW OFF
COMING NORTH AND THIRD IN LAKE COUNTY. IT'S IN THESE ABOVE MENTIONED
AREAS WHERE WERE CONCERNED FOR THUNDERSTORM DEVELOPMENT LATER THIS
AFTERNOON INTO THIS EVENING. THE CLOUD DEVELOPMENT IN SOUTHWEST
OREGON AND SISKIYOU COUNTY IS IN RESPONSE TO A SHORTWAVE THAT CAN BE
DEPICTED IN THE WATER VAPOR IMAGE NEAR 41N/124W. THIS WILL MOVE
NORTH AND THIS COULD BE ENOUGH TO BREAK THE CAP ALLOWING THINGS TO
BLOW UP IN THIS AREA. IN ADDITION GUSTY AND ERRATIC WINDS OF 40-50
MPH ARE A CONCERN WITH THESE STORMS WHICH WILL HAVE AN SIGNIFICANT
IMPACT ON FIRES.

EXPECT CONVECTION TO CONTINUE TONIGHT WITH A SOUTHEAST FLOW
ALOFT...SO THERE IS SOME CONCERN SOME OF THESE COULD MOVE WEST OF
THE CASCADES. I DID EXPAND THEM FARTHER WEST...BUT THE EVENING OR
NIGHT SHIFT MAY HAVE TO EXPAND THEM FURTHER IF THERE'S MORE EVIDENCE
SUPPORTING THIS IE SHORTWAVE ACTIVITY AND/OR SATELLITE TRENDS.

IT'S LIKELY WE'LL HAVE ANOTHER ACTIVE DAY THURSDAY WITH PLENTY OF
SHORTWAVES MOVING AROUND THE UPPER LOW. THE MID LEVEL FLOW IS
EXPECTED TO BECOME EAST TO SOUTHEAST AND STORMS THAT DEVELOP WILL
TEND TO MOVE WEST TO NORTHWEST OVER THE WEST SIDE. MOST STORMS ARE
NOT EXPECTED TO BE SEVERE...BUT COULD NOT RULE OUT A FEW ISOLATED
SEVERE IN DURING THE AFTERNOON. ADDITIONALLY THERE IS A BETTER
CHANCE FOR SOME STORMS TO PRODUCE LOCALLY HEAVY DOWNPOURS. ON THAT
NOTE...FELT THE SHREF GUIDANCE SEEMS TO HAVE A GOOD FIT...BUT DID
COMPROMISED BETWEEN IT AND THE NAM SOLUTIONS.

THE UPPER LOW WILL MOVE LITTLE THURSDAY NIGHT THROUGH FRIDAY AND
REMAINS AT OR JUST OFF THE OREGON COAST AND WILL SEND PLENTY OF
SHORTWAVES THROUGH THE AREA. SO WE'LL MOST LIKELY SEE SIMILAR
CONDITIONS AS THURSDAY.

THE UPPER LOW WILL SLOWLY MOVE NORTH SATURDAY. THE NAM SUGGEST MOST
OF THE CONVECTION WILL BE EAST OF THE CASCADES WHILE THE GFS AND EC
SHOW SOME IN SOUTHWEST OREGON. FOR NOW WE'LL LEAN TOWARDS THE GFS/EC
AND KEEP A SLIGHT CHANCE TO CHANCE OF STORMS OVER MOST OF THE
AREA.

BOTH THE GFS AND EC HAVE THE UPPER LOW CENTERED IN NORTHWEST OREGON
WITH A SOUTH TO SOUTHWEST FLOW ALOFT. THE GFS SHOWS SOME CONVECTION
BREAKING OUT ALONG AND EAST OF THE CASCADES. FOR NOW, MADE LITTLE
CHANCE TO THE FORECAST AS THE COVERAGE LOOKS REASONABLE.
-PETRUCELLI

&&

.FIRE WEATHER...THE FIRE WEATHER FORECAST CONTINUES TO BE ON TRACK
THIS AFTERNOON. WE RECORDED 300-600 STRIKES LAST NIGHT THROUGH THIS
MORNING OVER OUR FORECAST AREA, PRIMARILY CONCENTRATED OVER THE
CASCADES, BUT THERE WAS SOME ON THE WEST SIDE AS WELL. THIS RESULTED
IN AT LEAST 19 NEW FIRE STARTS THAT WE KNOW OF AND WE'VE HEARD THAT
INITIAL ATTACK HAS BEEN HEAVY IN THE CASCADES TODAY. THE STORMS WERE
GENERALLY DRY WITH A FEW SPOTS SHOWING A FEW 100THS OF AN INCH AS
THE STORMS PASSED AND NONE SHOWING ANYTHING CLOSE TO A WETTING RAIN.
THE SOUNDINGS INDICATE THAT MOISTURE HAS INCREASED SUBSTANTIALLY AND
THUS STORMS CONTINUE TO BECOME WETTER AND WILL OVER TIME.

ASIDE FROM THE STORMS WE EXPECT TO REDEVELOP THROUGH THE EVENING,
LOW LEVEL INSTABILITY IS GETTING RATHER EXTREME OVER THOSE AREAS
THAT ARE IN THE DRY/CLEAR SLOT (ROUGHLY FAR SW OREGON AND NW
CALIFORNIA). THE CONCERN HERE IS THAT GUSTY WINDS COULD MIX DOWN AND
TOGETHER WITH INSTABILITY WILL PROMOTE GROWTH OF NEW FIRES. ALSO, IF
WE ARE ABLE TO BREAK THE MID LEVEL CAP, NEW STORMS WILL GROW QUICKLY.

INSTABILITY, MOISTURE PARAMETERS, AND STEERING FLOW ARE SUCH THAT WE
THINK AT LEAST SCATTERED STORMS SHOULD CONTINUE DURING THE
AFTERNOONS AND EVENINGS THROUGH AT LEAST FRIDAY. WITH THE SOUTHEAST
FLOW ALOFT, THESE STORMS WILL MOVE INTO THE WEST SIDE AREAS AS WELL.
THUS THE RED FLAG WARNING HAS BEEN EXTENDED FOR ALL AREAS INLAND
FROM THE COAST THROUGH FRIDAY EVENING. DEPENDING ON HOW FUELS
RESPOND TO THE INCREASED MOISTURE (OR DON'T), THE RED FLAG WARNING
COULD BE CANCELED EARLY OR EXTENDED FURTHER IN TIME. WE WILL HAVE TO
WAIT AND SEE ON THAT. THE MODELS INDICATE MORE STABILITY CLOSE TO
THE COAST AND WHILE ISOLATED STORMS CAN'T BE RULED OUT EVEN THAT FAR
WEST, COVERAGE SHOULD BE MUCH LESS THAN INLAND AREAS. -WRIGHT

&&

.AVIATION...AREAS OF IFR CIGS/VSBYS ALONG THE COAST WILL SPREAD TO
THE REST OF THE COAST THIS EVENING AND INTO THE COASTAL VALLEYS
AND LOWER UMPQUA BASIN TONIGHT. THOSE AREAS WILL CLEAR BY THURSDAY
AFTERNOON.

EXPECT MAINLY VFR CONDITIONS INLAND...EXCEPT FOR AREAS OF
MVFR VSBYS AND LOCAL IFR VSBYS IN SMOKE...MOSTLY IN THE
SOUTHERN UMPQUA...ILLINOIS...AND ROGUE BASINS AS WELL AS SISKIYOU
COUNTY IN NORTHERN CALIFORNIA. ISOLATED TO SCATTERED THUNDERSTORMS
ARE EXPECTED ACROSS INLAND AREAS THROUGH THURSDAY. STORMS MAY BRING
VERY GUSTY AND ERRACTIC WINDS...BUT CONDITIONS WILL LIKELY REMAIN
VFR.

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...RED FLAG WARNING UNTIL 11 PM PDT FRIDAY FOR ORZ021>031.

CA...RED FLAG WARNING UNTIL 11 PM PDT FRIDAY FOR CAZ080>085.

PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS FROM 11 AM
     THURSDAY TO 5 AM PDT FRIDAY FOR PZZ376.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 11 AM THURSDAY TO 5
     AM PDT FRIDAY FOR PZZ376.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MEDFORD OR
326 PM PDT WED AUG 07 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0309 PM     HAIL             8 S APPLEGATE           42.14N 123.17W
08/07/2013  E0.50 INCH       JACKSON            OR   PUBLIC

            PUBLIC REPORTED HEAVY RAIN AND HAIL.

&&

DUNCAN

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MEDFORD OR
336 PM PDT WED AUG 7 2013

...TIME...  ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
...DATE...  ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0336 PM     HEAVY RAIN       3 ESE GRANTS PASS       42.43N 123.26W
08/07/2013  M0.00 INCH       JOSEPHINE          OR   TRAINED SPOTTER

            VISIBLITY REDUCED TO 1/8 MILE, FREQUENT
            LIGHTNING HEAVY RAIN DURATION 1 HOUR
            OBSERVER LOCATION ON ROGUE RIVER 3 MI E TOWN

&&

IRIS SYSTEM

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MEDFORD OR
410 PM PDT WED AUG 07 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0343 PM     HAIL             RUCH                    42.24N 123.04W
08/07/2013  E0.88 INCH       JACKSON            OR   PUBLIC

            HAIL REPORTED AS HALF THE SIZE OF GOLF BALLS OR ABOUT
            0.875 INCH HAIL. SPOTTER REPORTED HAIL WAS INCREASING IN
            SIZE AND THAT IT WAS RAINING VERY HEAVILY. REPORT FROM
            NORTH SIDE OF RUCH.

&&

LUTZ