Alert archive / Oregon / Freeze Warnings in 2007

Freeze Warning 3, NWS Medford, OR

April 9, 2007Douglas County, Oregon

NWS Medford, OR issued this freeze warning at Apr 9, 2007, 9:06 PM PDT for Douglas County, Oregon. It took effect at Apr 10, 2007, 3:00 AM PDT. It was in force for 6 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Apr 9, 2007, 9:06 PM PDT (04:06 UTC)
In effect from
Apr 10, 2007, 3:00 AM PDT
Expired
Apr 10, 2007, 9:00 AM PDT
In force
6 hr
Issued by
NWS Medford, OR

County Douglas County, OR

The radar

The Medford radar (KMAX), 139 km from the middle of the area, began a volume at 04:05 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Medford/Jackson, OR (KMFR), launched 00:00Z, 4.1 hours before the alert went out and 106 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Medford/Jackson, OR at 00:00Z on 2007-04-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 33 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Medford/Jackson, OR at 00:00Z on 2007-04-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 48 square meters per square second.1939587897117Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
33 J/kg
Mixed-layer CIN
-2 J/kg
Mixed-layer LCL
2071 m above ground
0-6 km bulk shear
78 kt
0-1 km storm-relative helicity
48 m²/s²
0-3 km storm-relative helicity
130 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this freeze warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Medford, OR wrote its last area forecast discussion before this freeze warning went out at Apr 9, 1:10 PM PDT, 7 hours 56 minutes earlier.

Area forecast discussion, Apr 9, 1:10 PM PDT, 7 hours 56 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
110 PM PDT MON APR 9 2007

.DISCUSSION...

TONIGHT BOTH THE GFS AND NAM SHOW A SLIGHT INCREASE IN SHOWERS
DUE TO A WEAK MID LEVEL DISTURBANCE AFTER MIDNIGHT MAINLY
AFFECTING SOUTHWEST OREGON.

TUESDAY MORNING SHOWERS END AS A SHORT WAVE RIDGE BUILDS
BUT BY LATE TUESDAY NIGHT RAIN RETURNS WITH A WARM FRONT
AHEAD OF A WEAK CLOSED LOW THAT CROSSES OUR AREA WEDNESDAY.
THE LATEST GFS RUN HAS WEAKENED THE LOW FURTHER YET 500MB
TEMPS WILL BE -25C COLD ENOUGH FOR ISOLATED THUNDER.

WEDNESDAY NIGHT EVEN COLDER COMES IN THE THE MAIN TROUGH
AXIS BUT BY MID DAY THURSDAY THE MAIN DYNAMICS WILL BE WELL
TO THE SOUTH. THE MORNING WILL BE COLD BUT CLOUDY. BY THE
AFTERNOON MOST SHOWERS WILL HAVE DISSIPATED AS THE NEXT
RIDGE BUILDS.

FRIDAY WILL BE DRY WITH A RETURN TO NEAR NORMAL AS 500MB
HEIGHTS CLIMB BACK TO 567DM. THEY QUICKLY FALL AGAIN AS A
COLD FRONT REACHES THE COAST SATURDAY MORNING CROSSING OUR
AREA DURING THE DAY. SUNDAY MORE COLD AIR SIDES OVER THE
REGION IN THE UPPER TROUGH AXIS. ANOTHER RIDGE BUILDS MONDAY
FOLLOWED BY ANOTHER COLD FRONT THE NEXT DAY.

&&

.AVIATION...LINGERING SHOWERS WILL PRODUCE ISOLATED MOUNTAIN
OBSCURATIONS TODAY OTHERWISE VFR. TONIGHT PATCHY MVFR WILL
OCCUR WITH ISOLATED SHOWERS. GENERALLY VFR TUESDAY APART FROM
MVFR IN THE MORNING IN THE UMPQUA BASIN.

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...NONE.

PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS
 UNTIL 5 PM PDT TUESDAY FOR PZZ350-PZZ356-PZZ370-PZZ376.

11

The office that day

Everything else NWS Medford, OR issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 9, 9:06 PM PDTFrost AdvisoryMFRCoos, Curry, Douglas, Jackson, Josephine12 hr

Nearby

Freeze Warnings in Oregon, 2007Every freeze warning in 2007

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.