A Frost Warning was issued for the above zones at 1544 PDT on 07/31/01. Observed low temperatures ranged from 40 to 48, which was likely due to overnight winds in the area.
Every event with a place to put it; 2 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
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.
The episode as NWS MFR wrote it up.
A Frost Warning was issued for the above zones at 1544 PDT on 07/31/01. Observed low temperatures ranged from 40 to 48, which was likely due to overnight winds in the area. The winds and the warmer than expected temperatures made frost very unlikely this night.
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 31, 7:30 PM PST, 4 hours 31 minutes earlier.
SOUTHWEST OREGON/NORTHERN CALIFORNIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
830 PM PDT TUE JUL 31 2001
MAIN FORECAST CONCERN FOR THIS UPDATE IS THE LOW TEMPERATURES INLAND
TONIGHT. RELATIVE HUMIDITIES ARE RUNNING AROUND 15 TO 20 PERCENT
LOWER AND RADIATIONAL COOLING FROM CLEAR SKIES WILL BRING
TEMPERATURES TO THE 40S WEST OF THE CASCADES AND 30S TO THE EAST.
FROST COULD BE A PROBLEM TONIGHT IN EXPOSED LOCATIONS. NEW MODEL RUN
LOOKS CONSISTANT AND DROPS A LOW PRESSURE TOWARD VANCOUVER ISLAND
WITH UPPER LEVEL TROUGH NEAR SHORE. COOLER MARINE AIR IS EXPECTED TO
FILTER INTO THE UMPQUA BASIN THURSDAY AND INTO THE ROGUE VALLEY ON
FRIDAY. COOLER AIR MAY NOT SPREAD EAST OF THE CASCADES AND SOUTH OF
THE SISKIYOUS UNTIL SATURDAY.
FB
.MFR...SMALL CRAFT ADVISORY CAPE BLANCO OREGON TO POINT ST GEORGE
CALIFORNIA.
...FROST WARNING TONIGHT FOR ORZ029-031 AND CAZ084>085.
OTH BB 048/068 054/067 054 080000
4BK BB 050/069 052/069 051 080000
RBG BU 048/082 055/083 055 080000
MFR UU 046/088 055/089 055 080000
LMT UU 035/084 046/085 045 080000
LKV UU 041/082 042/085 043 080000
MHS UU 045/083 051/084 050 080000The national radar mosaic for the moment the first event began.
2 extreme cold/wind chill. Local standard time, as filed.
See below.
See below.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2001Every state in 2001This day in weather historyWarnings in California, August 2001
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: 5257542, 5257543.