Extreme Cold in Oregon, July 16 to 17, 2001

Name: Extreme Cold in Oregon, July 16 to 17, 2001
Start: 2001-07-16T15:44
End: 2001-07-17T08:00
Location: Oregon

July 16 to 17, 2001 · NWS MFR · 3 events in 3 counties and zones

A Frost Warning was issued for the above zones effective at the above dates and times. Observed low temperatures ranged from 29 to 40.

Where it happened

Every event with a place to put it; 3 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 3

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS MFR wrote it up.

A Frost Warning was issued for the above zones effective at the above dates and times. Observed low temperatures ranged from 29 to 40. No frost was reported, but it likely did form this night.

What forecasters said that day

The local office's own words before the first event, 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 the first event at Jul 16, 1:30 PM PST, 2 hours 14 minutes earlier.

Area forecast discussion, Jul 16, 1:30 PM PST, 2 hours 14 minutes before

SOUTHWEST OREGON/NORTHERN CALIFORNIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
230 PM PDT MON JUL 16 2001

...UNSEASONABLY COOL...

THE COOL 500MB TROF WILL DOMINATE OVER THE PACIFIC NW THE NEXT FEW
DAYS. OTHER THAN UNSEASONABLY COOL TEMPS, A COUPLE SHORTWVS DIGGING S
INTO THE BASE OF THE TROF WILL CAUSE MARINE SURGES, AND OCASSIONAL
SHOWER OPPORTUNITIES OVER THE N ZONES. TODAYS ETA AND AVN HAVE
BETTER RESOLUTION OF THESE SHORTWVS AND FORECAST DETAILS FOLLOW THEIR
TIMING.

TONIGHT...MARINE STRATOCU DECK WILL DOMINATE THE UMPQUA BASIN...AND
LIKELY REDEVELOP OVER THE ROGUE BASIN. GENEROUS AFT CU FIELD, MODEL
PROGGED SOUNDINGS, AND MESOETA TIME/HGHT SECTIONS ALL SUPPORT THIS
SCENERIO. NGM/AVN DONT FULLY ACCOUNT FOR THIS, SO WILL HAVE TO SHOOT
A FEW DEGREES ABOVE GUIDANCE MIN TEMPS IN MEDFORD. OTHERWISE, FAIR WX
CU WILL COLLAPSE AFTER SUNSET OVER N CA AND E OF CASCADES...ALLOWING
FOR GOOD RADIATIONAL COOLING.

TUESDAY...MARINE STRATOCU WILL BREAK EARLY IN THE ROGUE BASIN AND NOT
TIL AFTERNOON IN THE UMPQUA. OTHERWISE, EXPECT A BATCH OF ALTOCU TO
MOVE ACROSS FORECAST AS AVN/NGM DEPICTED 315K ISENTROPIC ASCENT
RIPPLES THROUGH. PREFER WARMER AVN MOS (OVER NGM) WITH SUPPORT FROM
ETA LOW LEVEL THERMAL FIELDS. OVERALL TEMPS ABOUT 3F WARMER THAN
MONDAY.

TUE NIGHT...WEAK H5 SHORTWV DIGS AROUND BASE OF TROF THRU S OREGON.
LITTLE FORCING IS APPARENT, BUT WILL CARRY SLIGHT CHANCE OF SHOWERS
IN UMPQUA. TIME/HGHT SECTIONS ALSO SUGGEST THIS WILL SLOSH MARINE
LAYER OVER UMPQUA DIVIDE INTO THE ROGUE BASIN AGAIN. M CLEAR OVER N
CA AND EAST OF CASCADES.

WEDNESDAY...MORNING STRATOCU AGAIN BREAKS FIRST IN THE ROGUE BASIN
AND LATER IN THE UMPQUA. SCT FAIR WX CU EAST OF CASCADES. AGAIN...ETA
THERMAL FIELDS SUPPORT WARMER AVN MOS TEMPS.

EXTENDED...MODELS REMAIN CONSISTENT IN MAINTAINING WEAK 500MB
TROFFING AND NEGATIVE HEIGHT ANOMALIES ALONG W COAST WITH A BROAD HOT
RIDGE OVER THE S PLAINS. WHILE A WARMING TREND WILL OCCUR, THE TROF
WILL KEEP TEMPS FROM CLIMBING ABOVE NORMAL. ONE CHANGE IS THAT THE
MODELS ARE NOW BETTER RESOLVING A SHORTWV FEATURE CURRENTLY DIGGING
INTO SE ALASKA...ULTIMATELY EJECTING IT SOUTH INTO THE PACIFIC NW ON
THURSDAY. GIVEN ITS CURRENT SIGNATURE ON WV IMAGERY AND THE STRENGTH
OF THE IMPULSE, A CHANCE OF SHOWERS HAS BEEN INSERTED NORTH OF THE
UMPQUA DIVIDE FOR WED NIGHT AND THU. CLIMATOLOGY FOR LATE JULY ARGUES
AGAINST ANY PRECIP FURTHER SOUTH.

WOLF

.MFR...NONE.

OTH EE 051/065 051/065 053 141112
4BK BB 049/067 050/067 054 141111
RBG EE 051/073 051/075 054 141112
MFR BB 053/079 054/083 053 140000
LMT BB 039/073 043/078 043 140000
LKV BB 039/074 041/076 045 140000
MHS BB 045/074 045/078 048 140000

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

3 extreme cold/wind chill. Local standard time, as filed.

Extreme Cold/Wind Chill, Klamath Basin

When: July 16, 3:44 PM PST to July 17, 8:00 AM PST
Where: Klamath Basin forecast zone
Reported by: OFFICIAL NWS OBS.
Coordinates: 42.686, -121.650 (the zone’s center; the record gives no point)

See below.

Extreme Cold/Wind Chill, Northern & Eastern Klamath County & Western Lake County

When: July 16, 3:44 PM PST to July 17, 8:00 AM PST
Where: Northern & Eastern Klamath County & Western Lake County forecast zone
Reported by: OFFICIAL NWS OBS.
Coordinates: 42.740, -121.018 (the zone’s center; the record gives no point)

See below.

Extreme Cold/Wind Chill, Central & Eastern Lake County

When: July 16, 3:44 PM PST to July 17, 8:00 AM PST
Where: Central & Eastern Lake County forecast zone
Reported by: OFFICIAL NWS OBS.
Coordinates: 42.793, -120.387 (the zone’s center; the record gives no point)

See below.

What these are

Extreme Cold/Wind Chill: Temperatures or wind chills at or below the local warning criteria, or cold that caused deaths.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Oregon in 2001 Every state in 2001 This day in weather history Warnings in Oregon, July 2001

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 5256677, 5256678, 5256679.