Severe Weather from Texas to Pennsylvania

Over the last two days a strong low pressure system and vigorous cold front generated a smorgasbord of inclement weather across the central and eastern U.S., snow.

Loop of surface weather from 10:00 p.m. January 28 to 7:00 a.m. EST January 31.

This system generated the first widespread severe weather outbreak of the new year.  Severe thunderstorms occurred from Texas to Pennsylvania and through the Deep South.

Storm reports for January 29 (left) and January 30 (right).

Tornadoes touched down in Arkansas, Missouri, Louisiana, Kentucky, Tennessee, and Georgia. One person was killed and 14 were injured in Adairsville, Georgia when a tornado struck causing major damage. Eight people were injured near Calhoun, Georgia. Survey teams from the National Weather Service have been deployed to assess the damage and some information will be available later today. Visit the NWS Peachtree City (Atlanta) web site for the latest updates.


Heavy rain and snow melt earlier this week resulted sharp rises and ice break up on rivers and streams in Wisconsin, Illinois, Michigan, and Indiana have resulted in localized flooding. Flooding is likely to continue to be a threat through this weekend.

In the wake of this system, the rain changed to snow and a swath of 4 to 8  snow fell from Nebraska northeast through Wisconsin yesterday.

Although this powerful weather system has moved offshore, lake-effect snow and snow showers will continue today in the eastern U.S.

Crazy Winter Weather in the UK

M6 on Friday night

M6 in dark blue

 
Heavy snow Friday and Saturday paralyzed travel in western and northern England and Scotland. Motorists were stranded from 8 to 10 hours on M6, the longest and busiest highway in the UK.Stranded motorists entertained themselves building snowmen in the road, walking their dogs, and having snowball fights. Many cars were abandoned on the highway as well. In addition to closing numerous highways, the heavy snow caused a roof collapse, closed airport runways, and delayed rail travel.  Six inches of snow fell in many areas, with up to a foot reported. The Daily Mirror reported that a foot of snow fell in an hour, which is a rate not even seen in lake effect events. It is unlikely this rate occurred and other sources did not confirm this.


Now that the snow has ended, warmer temperatures and heavy rain are causing flooding problems in these same areas.Flooding is particularly serious in Wales, and rain is expected through Sunday morning.

The warning map for Sunday issued by the UK Met Office.

Rare Freezing Rain Event in Salt Lake City

Residents of Salt lake City woke up to some unusual weather conditions today. A light freezing rain that began before dawn was coating exposed surfaces with ice. The temperature when the precipitation started was only 20°F, and temperatures remained below freezing all day. There was only .09 inches of rain, but temperatures well below freezing it takes very little rain to create an icy mess.

Radar image from Salt Lake City at 5:00 MST January 24.

The glaze of ice turned roads, interstates, and parking lots into skating rinks. At 9:00 a.m. MST all runways of the Salt Lake City International Airport were closed to departures, and it was past mid afternoon before two runways could be opened. It was the first time in 24 years the airport was closed due to ice.Since 1940 there have been only nine other freezing rain events recorded at the airport. The 0.09 inches of freezing rain measured today was the greatest since December 31, 1983. There were dozens of weather-related accidents, and dispatchers reported more than 240 reports of other accidents and slide-offs. 

Freezing rain fell as far north as Boise, Idaho. The Idaho Transportation Department closed a 70-mile stretch of Interstate 84 between Boise and Glenns Ferry this morning, and schools closed because of the weather conditions.

Schematic of freezing rain formation.
Credit: University of Illinois Department of Atmospheric Sciences.

Freezing rain occurs when rain becomes supercooled and freezes on impact with objects on the surface. Typically snow falls though an elevated warm layer where the snow melts and becomes rain. The rain drops then fall through shallow layer of cold air near the surface, where they become supercooled. When the rain hits objects below freezing (the ground, trees, power lines, etc.) it immediately freezes.




The atmospheric sounding at Salt Lake City this morning exhibited this typical profile in fairly dramatic fashion.

Southwest flow ahead of a system approaching from the Pacific Northwest brought warm and moist air into the region at mid-levels while very cold air hugged the surface in the valleys. The cold air layer near the surface was only about 900 feet deep, while the warm layer immediately above was approximately 3700 feet deep. This set up the unusual freezing rain event in northern Utah this morning.

Read more here: http://www.idahostatesman.com/2013/01/24/2424526/freezing-rain-fell-all-night-in.html#storylink=cpy

Lake-Effect (and Pond-Effect) Snow

The lake-effect snow machine in full gear today as frigid Arctic air continues to stream over the open waters of the Great Lakes.

Surface temperature (left) and winds (right) at 11:00 EST

Regional radar at 11:21 EST

Visible satellite at 11:02 EST

Up to 6 inches of snow has fallen in southwestern Michigan, with another 1 to 3 inches expected today. Up to 15 inches of snow is possible in the western Michigan Upper Peninsula. In western New York a  Lake Effect Snow Warning is in effect until 10:00 EST Wednesday morning.  Six to 12 inches of snow are expected today, 6 to 12 tonight, and another 1 to 2 inches on Wednesday. This is on top of 12 to 18 inches in some areas as of this morning. A CoCoRaHS observer in Chautauqua County (NY-CQ-19, Ripley 4.3 SSW) had a 24-hour total of 18 inches this morning, with most of it falling before 7:00 p.m.last night. A Lake Effect Snow Warning is also in effect for northeastern Ohio, where one to three feet of snow may accumulate in the more persistent snow bands.

"Lake-effect" snow resulting from cold air streaming over smaller water bodies can occur as well. Snow bands developed downwind of a number of power plant cooling ponds in northern Illinois this morning.

5,400 Gray Dots

Today's CoCoRaHS national precipitation map was rather striking because of the lack of precipitation across the country. Of the 5,968 reports submitted as of this post, only 293 reported measurable precipitation, and of those 74 were just 0.01 inch.  There were also 264 trace reports.

A significant number of the measurable rainfall reports came from the east coast of Florida. Lake-effect snow produced some half-inch precipitation amounts and 4 to 8 inches of snow in northern Michigan. Snow also fell throughout much of Maine.

24-hour snowfall map for 7:00 a.m.local time January 20.

High pressure over much of the lower 48 states and a dry Arctic air mass pushing south is the reason why much of the country was precipitation-free.

Surface weather map for 9:00 p.m. CST January 20.

Winter Comes to Southern Appalachians

Winter Storm Warnings are in effect today and tonight for an area from east-central Mississippi through northern Georgia, much of western North Carolina, most of Virginia and Maryland.

Warnings and advisories in effect as of 11:00 a.m. EST January 17.
Pink areas designate Winter Storm Warnings, violet areas designate Winter Weather Advisories

Surface map at 7:00 a.m. EST January 17.

A low pressure system centered over northern Georgia will move east-northeast today. As cold air comes in behind this system rain will change to snow, and in some areas, freezing rain. The potential for the heaviest snow is in the mountains of eastern Tennessee, western North Carolina, and southwestern Virgina.

Probability of at least 4 inches of snow (left) and 8 inches of snow (right)
for the 24 hour period ending 7:00 EST Friday, January 18.

The good news is that high temperatures the next few days will be well above freezing and much of the snow will melt by early next week.

Maximum temperature forecast for Sunday, January 20.

Record Cold West, Record Warmth East

Low temperature records were set from Oregon and Utah south through southern California the past two days, while in the eastern U.S. record high temperatures were recorded in the southeast and mid-Atlantic.

Surface temperatures at 3:00 p.m EST January 14 (left), and at 7:00 a.m. PST January 15 (right).

The reason for this was a very amplified upper air pattern, with a ridge in the Pacific and a ridge in the Atlantic, with a broad and deep trough in between.

500 millibar map for January 14, 2013

In the west, strong northerly winds aloft brought air south from the Yukon and Northwest Territories. In the east, air was being drawn from the Pacific through Mexico and the Gulf of Mexico.

There were numerous record lows in the west the last two mornings.

LOCATION COUNTY RECORD PREVIOUS YEAR  Period of ARIZONA      Record WILLIAMS COCONINO                       -6 -5 1898 105 SHOW LOW AP NAVAJO                         0 0 1968 45 PARADISE COCHISE                        6 13 1922 31 PAYSON GILA                           8 8 1964 62 WILLCOX COCHISE                        9 9 1963 105 SAN SIMON COCHISE                        9 12 1944 54 BAGDAD YAVAPAI                        11 12 2007 73 DOUGLAS BISBEE INTL AP COCHISE                        11 11 1964 67 NATURAL BRG GILA                           11 11 1964 64 FT THOMAS 2 SW GRAHAM                         11 15 1992 42 AGUILA MARICOPA                       14 15 1964 60 TUZIGOOT YAVAPAI                        15 16 2007 35 SASABE PIMA                           15 19 1963 46 WIKIEUP MOHAVE                         17 19 1964 50 WITTMANN 4SW MARICOPA                       18 20 1963 34 TUCSON INTL AP PIMA                           21 23 1963 68 FOUNTAIN HILLS MARICOPA                       23 31 1992 30 CALIFORNIA BODIE CA ST HISTORIC PARK MONO                           -27 -26 2007 58 JESS VALLEY MODOC                          -13 -5 1962 62 SOUTH LAKE TAHOE AP EL DORADO                      -11 -7 1997 43 TULELAKE SISKIYOU                       -5 -4 1962 76 MC CLOUD SISKIYOU                       5 7 1932 96 SANDBERG LOS ANGELES   15 20 2007 64 DAGGETT AP SAN BERNARDINO  16 16 1963 64 MT WILSON CBS LOS ANGELES  16 18 1962 59 CACHUMA LAKE SANTA BARBARA 21 25 1955 55 BORREGO DESERT PARK SAN DIEGO                      27 28 2007 45 LOS ANGELES DWTN USC LOS ANGELES 34 36 2007 99 IDAHO STANLEY CUSTER                         -32 -30 1923 51 GRACE CARIBOU                        -24 -20 2007 101 MAY 2SSE LEMHI                          -20 -15 1960 65 CHILLY BARTON FLAT CUSTER                         -20 -20 1964 62 IDAHO FALLS FAA AP                                -19 -17 1964 53 MACKAY LOST RIVER RS CUSTER                         -18 -18 1932 101 CRATERS OF THE MOON BUTTE                          -15 -9 2007 52 PALISADES BONNEVILLE                     -14 -12 1962 51 PRESTON FRANKLIN                       -14 -10 1985 37 PAUL 1ENE MINIDOKA                       -13 -4 1985 73 IDAHO CITY BOISE                          -13 -11 1930 100 MIDDLE FORK LODGE CUSTER                         -8 -8 2007 41 NAMPA SUGAR FACTORY CANYON                         2 3 1986 31 NEW MEXICO NAVAJO DAM SAN JUAN                       1 2 1975 46 GRAN QUIVIRA NATL MON SOCORRO                        2 2 1964 76 COCHITI DAM SANDOVAL                       3 5 1977 32 GLENWOOD CATRON                         7 9 1964 60 HACHITA GRANT                          9 9 1989 84 NEVADA MONTELLO 2NE ELKO                           -27 -14 1932 99 ELY AIRPORT WHITE PINE                     -24 -17 2007 81 RUTH WHITE PINE                     -24 -19 2007 44 BEOWAWE EUREKA                         -21 -20 1962 94 MCGILL WHITE PINE                     -20 -13 2007 104 RUBY LAKE NWR ELKO                           -17 -8 1964 70 BLUE EGLE CURRANT12SSW NYE                            -15 -13 1985 30 OROVADA 3 W HUMBOLDT                       -14 -14 1917 96 LOVELOCK DERBY FLD AP PERSHING                       -12 -9 1962 60 SUNNYSIDE - LUND 31S NYE                            -7 -7 1989 47 DENIO HUMBOLDT                       -3 3 2005 54 TONOPAH NYE                            -3 8 1932 31 PIOCHE LINCOLN                        1 2 1997 78 AMARGOSA FARMS-GAREY NYE                            14 17 1989 36 SEARCHLIGHT CLARK                          15 19 2007 94 OREGON BURNS MUNI AP HARNEY                         -11 -4 1989 40 HART MTN REFUGE LAKE                           -10 -3 1962 66 HOWARD PRAIRIE DAM JACKSON                        -6 2 1962 51 LONG CREEK GRANT                          2 2 1997 50 MONUMENT 2 GRANT                          5 8 1997 41 MARION FRKS FISH HATCH LINN                           7 8 2007 63 TOKETEE FALLS DOUGLAS                        15 16 2007 57 IDLEYLD PARK 4 NE DOUGLAS                        18 19 1997 52 UTAH BRYCE CANYON FAA AP                                -30 -13 2007 42 TRENTON CACHE                          -27 -14 1985 34 EPHRAIM SANPETE                        -26 -21 2007 58 PINE VIEW DAM WEBER                          -22 -22 1964 69 SCIPIO MILLARD                        -22 -21 2007 107 NEOLA DUCHESNE                       -19 -16 2007 49 DEER CREEK DAM WASATCH                        -17 -15 1955 73 HEBER WASATCH                        -16 -16 1964 118 VERNON TOOELE                         -16 -7 1964 45 SANTAQUIN CHLORINATOR UTAH                           -12 -9 2007 92 KANOSH MILLARD                        -7 2 1964 42 HANS FLAT RS WAYNE                          -4 2 1989 32 ARCHES NP HQS GRAND                          -4 -3 1989 32 BOUNTIFUL-VAL VERDA DAVIS                          -3 2 2007 32 NATURAL BRIDGES NM SAN JUAN                       -3 0 2011 45 CEDAR POINT SAN JUAN                       -3 0 1989 50 WENDOVER AP AWOS TOOELE                         -2 0 2007 99 CANYONLANDS-THE NECK SAN JUAN                       -1 2 1989 45 CAPITOL REEF NP WAYNE                          0 2 1989 45 BULLFROG BASIN KANE                           9 11 1968 35

Record maximum temperatures were concentrated in the the southeastern U.S. on Monday, but were recorded as far north as Maine and New Hampshire, including a record tied at Mt. Washington.

LOCATION	COUNTY	REC	PREV	YEAR	POR
ALABAMA
DOTHAN FAA AP	HOUSTON	79	79	1947	70
GENEVA #2	GENEVA	78	76	2007	36
CENTREVILLE 6 SW	BIBB	73	71	2007	38
OPELIKA	LEE	72	72	2000	52
ARKANSAS
WEST MEMPHIS	CRITTENDEN	70	67	1995	46
FLORIDA
CLERMONT 9 S	LAKE	83	83	2005	61
INVERNESS 3 SE	CITRUS	83	83	1992	88
MAYO	LAFAYETTE	82	82	1950	61
GAINESVILLE RGNL AP	ALACHUA	82	81	1999	50
JACKSONVILLE INTL AP	DUVAL	81	80	1950	65
TALLAHASSEE WSO AP	LEON	81	80	1971	67
JASPER	HAMILTON	81	81	1972	58
FERNANDINA BEACH	NASSAU	80	80	1972	111
PERRY	TAYLOR	79	77	2007	69
QUINCY 3 SSW	GADSDEN	78	78	1989	39
GEORGIA
SAVANNAH INTL AP	CHATHAM	81	78	2007	68
ALMA BACON CO AP	BACON	80	79	2007	64
MILLEDGEVILLE	BALDWIN	80	76	1937	112
AUGUSTA BUSH FLD AP	RICHMOND	80	73	2007	68
HOMERVILLE 5 N	CLINCH	79	79	1960	55
ALBANY CAA AP		79	79	2007	37
COLUMBUS METO AP.	MUSCOGEE	78	75	1960	65
PLAINS SW GA EXP STN	SUMTER	77	77	1960	56
ASHBURN 3 ENE	TURNER	77	77	1960	51
SAPELO ISLAND	MCINTOSH	77	77	2000	46
SANDERSVILLE	WASHINGTON	76	76	1960	52
CARTERSVILLE	BARTOW	75	71	1960	66
SILOAM 3N	GREENE	75	73	2000	52
ATHENS BEN EPPS AP	CLARKE	74	71	2007	68
LA GRANGE 1N	TROUP	74	73	1937	71
ALLATOONA DAM 2	BARTOW	74	72	1995	48
LOUISIANA
CLINTON 5 SE	EAST FELICIANA	79	77	2000	34
MARYLAND
FROSTBURG 2	ALLEGANY	62	62	2005	40
MAINE
AUGUSTA STATE AIRPORT	KENNEBEC	55	54	2006	64
CARIBOU WFO	AROOSTOOK	52	51	2005	72
MISSISSIPPI
YAZOO CITY 5 NNE	YAZOO	81	77	2007	52
WAYNESBORO 2 W	WAYNE	79	78	1971	90
FULTON 3 W	ITAWAMBA	72	72	2007	54
NORTH CAROLINA
ELIZABETH CITY FAA AP		79	74	1952	42
NEW BERN - ASOS	CRAVEN	79	74	2007	64
GREENVILLE	PITT	78	78	1932	84
WILMINGTON INTL AP	NEW HANOVER	77	75	1950	80
PLYMOUTH 5 E	WASHINGTON	76	76	2005	65
LEWISTON	BERTIE	75	75	1995	51
LONGWOOD	BRUNSWICK	75	75	2005	38
CONCORD	CABARRUS	74	74	2005	77
BURLINGTON FIRE STN #5	ALAMANCE	74	74	2005	59
ROXBORO 7 ESE	PERSON	74	72	1960	62
SILER CITY 2 N	CHATHAM	74	74	2005	81
REIDSVILLE 2 NW	ROCKINGHAM	73	71	2005	49
PISGAH FOREST 3 NE	TRANSYLVANIA	72	68	2005	71
YADKINVILLE 6 E	YADKIN	71	70	2005	55
ENKA	BUNCOMBE	71	70	2007	41
NORTH WILKESBORO	WILKES	71	70	2005	55
FRANKLIN	MACON	70	68	1952	64
W KERR SCOTT RSVR	WILKES	70	69	2005	47
MURPHY	CHEROKEE	68	68	2005	44
JEFFERSON 2 E	ASHE	67	63	2007	82
TRANSOU	ASHE	63	63	2007	65
BOONE 1 SE	WATAUGA	62	62	2007	31
GRANDFATHER MTN	AVERY	57	54	2007	55
GREENLAND	ROCKINGHAM	60	60	2005	37
NEW HAMPSHIRE
LEBANON CAA AP	GRAFTON	55	51	2006	46
MT WASHINGTON	COOS	43	43	2005	64
NEW YORK
AVON	LIVINGSTON	68	64	1995	83
DANSVILLE	LIVINGSTON	67	66	1995	86
WARSAW 6 SW	WYOMING	64	57	2006	59
PENNSYLVANIA
RIDGWAY	ELK	69	67	1972	98
MONTGOMERY L&D	BEAVER	68	66	1995	49
TIONESTA 2 SE LAKE	FOREST	68	68	2005	67
CHALK HILL 2 ENE	FAYETTE	64	62	1995	35
BRADFORD 4SW RES 5	MCKEAN	63	60	2006	65
SOUTH CAROLINA
COLUMBIA UNIV OF SC	RICHLAND	82	80	1932	80
COLUMBIA METRO AP	LEXINGTON	81	73	2005	68
DILLON	DILLON	81	81	1907	81
SUMMERVILLE 4W	DORCHESTER	80	80	1907	111
FLORENCE RGNL AP	FLORENCE	79	75	1995	65
CHARLESTON INTL. AIRPORT	CHARLESTON	79	78	1932	83
JOHNSTON 4 SW	EDGEFIELD	78	73	2000	54
BISHOPVILLE 1ENE	LEE	77	77	2005	71
SANDHILL RSCH ELGIN	RICHLAND	77	72	1995	51
MCCOLL 3 NNW	MARLBORO	77	75	1937	75
BAMBERG	BAMBERG	76	72	2005	58
ANDREWS	GEORGETOWN	76	75	2005	42
PELION 4 NW	LEXINGTON	76	72	2005	50
LAURENS	LAURENS	75	75	1937	94
MANNING	CLARENDON	75	75	2007	38
NINETY NINE ISLANDS	CHEROKEE	73	71	2005	50
TENNESSEE
ERWIN 1 W	UNICOI	74	71	2005	33
KNOXVILLE EXP STN	KNOX	71	71	1995	32
ATHENS	MCMINN	70	70	2005	48
VIRGINIA
SOUTH BOSTON	HALIFAX	73	73	2005	31
MARTINSVILLE FLTR PLT	HENRY	72	70	2007	64
PULASKI 2 E	PULASKI	71	63	2007	56
APPOMATTOX	APPOMATTOX	70	69	1995	46
STAFFORDSVILLE 3 ENE	GILES	70	65	2005	42
WYTHEVILLE 1 S	WYTHE	70	70	1932	94
BLACKSBURG NWSO	MONTGOMERY	69	65	1960	58
WEST VIRGINIA
SNOWSHOE	POCAHONTAS	54	52	2005	36