Barometers Showing Low Pressure on Oct 26, 2010
Courtesy: Minnesota State Climatology Office
An extremely strong low-pressure system on October 26-27 set sea-level pressure pressure records in Minnesota and produced widespread damaging winds associated with the storm's powerful and massive circulation.
The storm system began as an area of low pressure emerged from the Bighorn Mountains in eastern Wyoming on October 25th. The system was already quite strong at that time, and the ingredients aloft were nearly perfect for a period of rapid intensification. By evening of the 26th, the storm had hooked northward towards the Minnesota/Canada border and had already broken Minnesota record for lowest sea-level pressure. For a period of over 36 hours, from the 26th into the 27th, strong winds raged across a huge swath of central North America, as the storm's circulation sprawled across a large portion of the continent.
High Wind Warnings were posted from southeast Montana to Ohio, with Blizzard Warnings over a much of North Dakota. The strongest wind gust reported in Minnesota was 65 mph at both Georgeville in Stearns County, and Mehurin Township in Lac Qui Parle County.
This is one of the strongest non-tropical storms on record for lowest minimum pressure in the United States. The lowest pressure found, after adjusting for the true mean sea level pressure, was 28.21 inches (955.2 millibars) at 5:13 pm at Bigfork in Itasca County. This shatters the old Minnesota lowest pressure record of 28.43 inches (962.7 millibars) that was set in the November 10, 1998 storm at both Austin and Albert Lea.
To illustrate how strong of a storm this is, 28.21 inches is equivalent to a Category 3 Hurricane. The lowest pressure for the storm that sank the Edmund Fitzgerald on November 10, 1975 was 28.95 inches. Even with the Armistice Day storm, the lowest pressure recorded was 28.55 inches. Of course, pressure is only one measure of a storm's intensity.
During the evening hours of October 26, snow became mixed with the rain over northern Minnesota, by daybreak on October 27, a white blanket of snow covered parts of northern Minnesota. The heaviest snow total found so far was near Twig in St. Louis County with 9 inches. The Duluth National Weather Service Office measured 7.4 inches. Heavy rains also fell with this storm. with 3 to 5.5 inches reported in portions of northeastern Minnesota.
The Duluth and Chanhassen offices of the National Weather Service compiled summaries of this historic weather system.
Listed below are Public Information Statements and Storm Summaries from the National Weather Service. More details can be found here for the October 26-27 storm.
STORM SUMMARY NUMBER 7 FOR MIDWEST HIGH WIND EVENT
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
1000 AM CDT WED OCT 27 2010
...RECORD BREAKING LOW PRESSURE SYSTEM BEGINS TO WEAKEN AS IT
MOVES INTO ONTARIO CANADA...
BLIZZARD WARNINGS...WINTER STORM WARNINGS....AND WINTER WEATHER
ADVISORIES ARE IN EFFECT ACROSS MUCH OF NORTH DAKOTA...NORTHERN
MINNESOTA...EXTREME NORTHWESTERN WISCONSIN...AND NORTHEASTERN
MONTANA.
HIGH WIND WATCHES...WARNINGS AND WIND ADVISORIES REMAIN IN EFFECT
FOR AN EXTENSIVE AREA ACROSS MUCH OF THE NORTHERN PLAINS INTO
PARTS OF THE CENTRAL PLAINS...THE MIDWEST...UPPER GREAT
LAKES...AND THE NORTHERN OHIO VALLEY. STORM WARNINGS ARE IN EFFECT
FOR PORTIONS OF THE WATERS OF THE GREAT LAKES.
FOR A DETAILED GRAPHICAL DEPICTION OF THE LATEST
WATCHES...WARNINGS AND ADVISORIES...PLEASE SEE WWW.WEATHER.GOV
AT 900 AM CDT...A STRONG LOW PRESSURE SYSTEM WITH A CENTRAL
PRESSURE OF 969 MB...28.61 INCHES...WAS LOCATED OVER SOUTHERN
ONTARIO...NEAR PICKLE LAKE. NATIONAL WEATHER SERVICE RADARS AND
SURFACE OBSERVATIONS INDICATED AREAS OF LIGHT TO OCCASIONALLY
MODERATE RAIN AND SNOW ACROSS PORTIONS OF THE NORTHERN PLAINS AND
MIDWEST. WINDS WERE GENERALLY 20 TO 30 MPH SUSTAINED...WITH GUSTS
AS HIGH AS 40 TO 50 MPH...PARTICULARLY ACROSS THE DAKOTAS.
...SELECTED STORM TOTAL SNOWFALL IN INCHES FROM 1200 PM CDT MON
OCT 25 THROUGH 800 AM CDT WED OCT 27...
...MINNESOTA...
DULUTH 7.4
TWO HARBORS 7 NW 7.1
CLOQUET 4 WNW 5.0
TWIG 5 SE 5.0
HEWITT 0.3 ENE 4.0
UNDERWOOD 7.6 NNW 4.0
...NORTH DAKOTA...
HARVEY 8.0
GRENORA 6.0
MINOT 4.0
WILLISTON 3.1
BISMARCK 5 NW 2.5
KILLDEER 0.6 WNW 2.5
LINTON 5 WNW 2.5
...SELECTED PEAK WIND GUSTS IN MILES PER HOUR EARLIER IN THE
EVENT...
...IOWA...
BOONE AIRPORT 4 ESE 58
ORANGE CITY 58
SPENCER 58
WAUKON 51
ESTHERVILLE AIRPORT 50
IONIA 2 N 49
CHARLES CITY 3 E 45
...ILLINOIS...
MACKINAW 1 NE 70
DUPAGE AIRPORT 61
FAIRVIEW 60
LAWRENCEVILLE AIRPORT 60
OSKALOOSA 60
JACKSONVILLE 58
OLNEY 57
FLORA 1 E 56
PETERSBURG 8 E 55
...INDIANA...
GREENFIELD 77
SW MONROEVILLE 75
MOORESVILLE 2 NW 70
TERRE HAUTE 70
ODON 68
SHERIDAN 68
NORMAL 1 N 67
COLUMBIA CITY 65
ANDERSON 5 N 63
INDIANAPOLIS 61
...MICHIGAN...
POINT AUX BARQUES 3 W 71
FREDA 69
GRAND MARAIS 68
DAVISON 65
SOUTH HAVEN 1 W 64
ESCANABA 58
MUSKEGON 4 W 58
PLOVER 58
FAIRPORT 56
CADILLAC 54
...MINNESOTA...
GEORGEVILLE 65
MEHURIN 65
HANLEY FALLS 63
LAKE BENTON 62
MORRIS 62
SAUK CENTRE 62
ALEXANDRIA 61
LANGHEI 61
GLENWOOD 60
MINNEAPOLIS 60
ST. CLOUD 50
...MONTANA...
COMERTOWN 6 S 60
...NORTH DAKOTA...
FARGO/HECTOR FIELD 64
BISMARCK 61
HETTINGER 61
MANDAN 4 S 60
JAMESTOWN 59
ADAMS 58
GARRISON 58
DICKINSON 56
MINOT 54
WILLISTON 47
LINTON 46
...NEBRASKA...
ONEILL 55
GRAND ISLAND 54
OGALLALA 54
VALENTINE 54
BROKEN BOW 51
ORD 47
HASTINGS 45
...SOUTH DAKOTA...
UNION CENTER 70
SISSETON 64
ABERDEEN 62
CASTLEWOOD 62
FAITH 62
RAPID CITY/ELLSWORTH AFB 62
BUFFALO 1 N 61
DRAPER 4 NNE 61
MOBRIDGE 1 ENE 61
PHILIP 3 E 61
OACOMA 60
PIERRE MUNI ARPT 60
...WISCONSIN...
SHERWOOD 76
ALGOMA 68
ALGOMA CITY MARINA 68
KENOSHA MUNI ARPT 68
SHIOCTON 4 W 59
PLOVER 58
BELLEVUE 57
EYOTA RWIS 2 SE 56
VIROQUA AWOS 56
GREENVILLE 55
LA CROSSE 3 E 50
THE SURFACE LOW IS EXPECTED TO STEADILY WEAKEN TODAY AS IT
CONTINUES TO MOVE EAST-NORTHEASTWARD INTO CANADA. BLIZZARD OR NEAR
BLIZZARD CONDITIONS ARE POSSIBLE WITHIN THE WARNED AREA TODAY.
CONDITIONS SHOULD IMPROVE ACROSS THE REGION BY THIS EVENING AS THE
PRESSURE GRADIENT DECREASES CAUSING THE WINDS TO RELAX. LIGHT RAIN
AND SNOW SHOWERS WILL CONTINUE TO BE POSSIBLE ACROSS THE REGION
THROUGH EARLY THURSDAY MORNING HOWEVER.
THE NEXT STORM SUMMARY WILL BE ISSUED BY THE HYDROMETEOROLOGICAL
PREDICTION CENTER AT 400 PM CDT. PLEASE REFER TO YOUR LOCAL
NATIONAL WEATHER SERVICE OFFICE FOR ADDITIONAL INFORMATION ON THIS
EVENT.
PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE DULUTH MN
845 AM CDT WED OCT 27 2010
...LOW PRESSURE RECORDS BROKEN ON OCTOBER 26 2010...
THIS IS A PRELIMINARY STATEMENT ON THESE PRESSURE RECORDS. HERE IS
WHAT WE KNOW SO FAR ABOUT THE LOW PRESSURE RECORDS SET ON OCTOBER
26TH:
AN UNUSUALLY INTENSE LOW AFFECTED THE STATE OF MINNESOTA. AT 513 PM
CDT...THE AUTOMATED WEATHER OBSERVING SYSTEM AT BIGFORK MINNESOTA
RECORDED A 954.96 MILLIBAR /28.20 INCHES/ PRESSURE. THIS BREAKS THE
ALL TIME MINNESOTA STATE RECORD FOR THE LOWEST OBSERVED PRESSURE.
THE PREVIOUS RECORD WAS 962.6 MB SET ON NOVEMBER 10 1998 AT ALBERT
LEA AND AUSTIN IN SOUTHERN MINNESOTA. THE RECORD WAS INITIALLY
BROKEN SHORTLY AFTER 10 AM AS THE LOW PASSED BY AITKIN MINNESOTA.
HOWEVER...THE LOW CONTINUED TO INTENSIFY INTO THE AFTERNOON.
.DULUTH...THE LOW PRESSURE RECORD AT DULUTH WAS SET AT 1113 AM
WITH A PRESSURE OF 960.72 MILLIBARS /28.37 INCHES/. THE PREVIOUS
RECORD WAS 964.3 MILLIBARS WHICH OCCURRED ON NOVEMBER 10 1998.
.INTERNATIONAL FALLS...THE LOW PRESSURE RECORD AT INTERNATIONAL
FALLS WAS SET AT 345 PM WITH A PRESSURE OF 955.98 MILLIBARS /28.23
INCHES/. THE PREVIOUS RECORD WAS 971.9 MILLIBARS ON OCTOBER 10 1949.
.WISCONSIN...THE LOW PRESSURE RECORD FOR THE STATE OF WISCONSIN WAS
SET IN SUPERIOR AT 1115 AM WITH A PRESSURE OF 961.06 MILLIBARS
/28.38 INCHES/. THE PREVIOUS RECORD WAS 963.4 MILLIBARS WHICH
OCCURRED AT GREEN BAY ON APRIL 3 1982.
...LOWEST BAROMETRIC PRESSURE RECORD SET IN LA CROSSE WI...
AT 553 AM ON OCTOBER 26TH...THE BAROMETRIC PRESSURE FELL TO
971.4 MILLIBARS /28.685 INCHES OF MERCURY/. THIS JUST BARELY BEAT
THE PREVIOUS RECORD OF 971.6 MILLIBARS /28.691 INCHES OF MERCURY/
ON NOVEMBER 10 1998. THE TABLE BELOW CONTAINS THE FIVE LOWEST
BAROMETRIC PRESSURES AT LA CROSSE WI SINCE 1933.
LOWEST BAROMETRIC PRESSURE READINGS
AT LA CROSSE WI
1933 TO PRESENT
SEA LEVEL
SEA LEVEL PRESSURE
PRESSURE IN INCHES
RANK IN MILLIBARS OF MERCURY DATE TIME
---- ------------ ---------- ---- ----
1 971.4 28.685 10/26/2010 553 AM
2 971.6 28.691 11/10/1998 150 PM
3 971.9 28.700 04/03/1982 900 AM
4 973.6 28.750 11/11/1940 700 PM +
5 973.8 28.756 01/11/1975 500 AM
+ ARMISTICE DAY STORM
...THIRD LOWEST BAROMETRIC PRESSURE IN ROCHESTER MN...
AT 654 AM ON OCTOBER 26TH...THE BAROMETRIC PRESSURE FELL TO
972.9 MILLIBARS /28.73 INCHES OF MERCURY/ AT ROCHESTER INTERNATIONAL
AIRPORT. THIS WAS THIRD LOWEST BAROMETRIC PRESSURE. THE LOWEST
PRESSURE AT ROCHESTER WAS 964.8 MILLIBARS /28.49 INCHES OF MERCURY/
ON NOVEMBER 10 1998. THE TABLE BELOW CONTAINS THE FIVE LOWEST
BAROMETRIC PRESSURES AT ROCHESTER MN SINCE 1948.
LOWEST BAROMETRIC PRESSURE READINGS
AT ROCHESTER MN
1948 TO PRESENT
SEA LEVEL
SEA LEVEL PRESSURE
PRESSURE IN INCHES
RANK IN MILLIBARS OF MERCURY DATE
---- ------------ ---------- ----
1 964.8 28.49 11/10/1998
2 971.1 28.67 01/11/1975
3 972.9 28.73 10/26/2010
4 974.9 28.79 03/27/1950
5 975.7 28.81 04/03/1982
PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
800 PM CDT TUE OCT 26 2010
...PUBLIC INFORMATION STATEMENT...
...SUMMARY OF THE PEAK WIND GUSTS IN SOUTHERN MINNESOTA
AND WEST CENTRAL WISCONSIN ON TUESDAY...
LOCATION PEAK GUST TIME OF PEAK GUST
------------------------------------------------------------
...AUTOMTED ASOS AND AWOS SITES...
APPLETON 63 MPH 5:14 PM TUE
MORRIS 62 MPH 5:12 PM TUE
ALEXANDRIA 61 MPH 5:27 PM TUE
GLENWOOD 60 MPH 3:34 PM TUE
OLIVIA 60 MPH 4:53 PM TUE
MINNEAPOLIS 60 MPH 7:04 PM TUE
CANBY 60 MPH 6:34 PM TUE
BENSON 59 MPH 2:33 PM TUE
GRANITE FALLS 59 MPH 3:33 PM TUE
ST. JAMES 59 MPH 2:55 PM TUE
REDWOOD FALLS 57 MPH 2:53 PM TUE
MARSHALL 57 MPH 2:15 PM TUE
NEW ULM 56 MPH 2:55 PM TUE
REWOOD FALLS 55 MPH 4:16 PM TUE
PAYNESVILLE 53 MPH 3:53 PM TUE
WILLMAR 53 MPH 2:56 PM TUE
MONTEVIDEO 52 MPH 2:34 PM TUE
ST. CLOUD 50 MPH 3:53 PM TUE
HUTCHINSON 49 MPH 2:52 PM TUE
MANKATO 47 MPH 2:35 PM TUE
OWATONNA 47 MPH 2:54 PM TUE
GLENCOE 47 MPH 6:53 PM TUE
ST. PAUL 44 MPH 3:53 PM TUE
EAU CLAIRE 44 MPH 2:56 PM TUE
FLYING CLOUD AIRPORT 44 MPH 3:53 PM TUE
LAKEVILLE 42 MPH 4:14 PM TUE
MENOMONIE 41 MPH 2:36 PM TUE
...AUTOMATED MESONET DATA...
MEHURIN 65 MPH 4:23 PM TUE
GEORGEVILLE 65 MPH 6:01 PM TUE
HANLEY FALLS 63 MPH 2:10 PM TUE
SAUK CENTER 62 MPH 4:03 PM TUE
LANGHEI 61 MPH 2:16 PM TUE
GEORGEVILLE 59 MPH 4:11 PM TUE
LESTER PRAIRIE 55 MPH 3:54 PM TUE
BELLE PLAINE 52 MPH 3:47 PM TUE