The Bitterly Cold Air of January 27th-28th, 2014

The Bitterly Cold Air of January 27th-28th

Fast Facts | Science & Photos | Temperatures | Wind Chills | Wind Gusts

Fast Facts

Chicago (O'Hare) dropped to -11°F on the morning of January 28th. Chicago (Midway) also dropped to -11°F.
This was the 15th day below 0° in Chicago. This is the most since the 1993-1994 winter (17 days).
The lowest wind chill observed at Chicago O'Hare and downtown Chicago was -30°F early on the morning of the 28th.
Rockford dropped to -18°F on the morning of January 28th, which was the coldest temperature since -18°F on January 6th and 3rd earlier in the month. This was the coldest temperature of the winter.
The last winter Rockford had three mornings of -18°F or lower was the 1995-1996 winter (4 times).
The lowest wind chill at Rockford was -30°F on the morning and night of January 27th.
The lowest temperature in the area on the morning of January 28th was -19°F in Marengo in McHenry County.
The lowest wind chills observed were -34°F to -35°F across Lee, Ogle, and DeKalb Counties.

Science & Photos

Sundogs
Romeoville	Oswego	Wilmington

Sundogs are a pair of brightly colored spots on the circumference of the sun halo, often located directly apart from each other. They form as a result of sunlight being refracted by ice crystals. These are most commonly caused by cirrus clouds which are composed of ice crystals. However, crystals are present in the lower atmosphere on January 27th due to both blowing snow, as well as scattered light cloud development. Because the lower atmosphere is so cold any of these lower clouds are composed of ice crystals. This is leading to frequent sundogs across northern Illinois and northwest Indiana! We thank our NWS Chicago Facebook fans for the photos.

The weather pattern on January 27th-28th was similar to that of three weeks prior, on January 6th-7th that brought the last Arctic air outbreak to northern Illinois and northwest Indiana. Here is a quick look at the 500mb map, as well as an explanation from the similar January 6th-7th event:

For a high resolution image click here.

The upper air pattern related to a section of the polar vortex, which became a viral term during the last cold air outbreak. For more on this, please see this helpful graphic from our colleagues at the New York NWS office.

One final factor that has helped with the cold, including this deep cold outbreak, is snow cover. Snow cover serves as almost a "freezer", preserving the cold air mass as it works southward. During the daytime, it also reflects much of the sun's short wave energy, not allowing for as much heating. Below one can see the substantial amount and depth of snow cover on Jan 27th, not only over the immediate area but "upstream" for northwest winds.

January 27th Regional Snow Depth

January 27th National Snow Depth

Images courtesy of the National Operational Hydrologic Remote Sensing Center

Temperatures

January 28th Morning:

MAXIMUM/MINIMUM TEMPERATURE AND PRECIPITATION TABLE
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
830 AM CST TUE JAN 28 2014

HIGH TEMPERATURE YESTERDAY
LOW TEMPERATURE ENDING AT 6 AM
PRECIPITATION LAST 24 HOURS
SNOWFALL LAST 24 HOURS

.BR LOT 0128 C DH00/TAIRZX/DH06/TAIRZP/PPDRZZ/SFDRZZ

:ID  LOCATION                  HIGH   LOW    PCPN  SNOWFALL
ORD: CHICAGO-O`HARE         :   6  /  -11  /  0.00  / 0.0
CNII2: CHICAGO-NORTHERLY ISL:   8  /  -9  /
MDW: CHICAGO-MIDWAY         :   6  /  -11  /  0.00
LOTI2: NWS ROMEOVILLE       :   4  /  -15  /  0.00  /
RFD: ROCKFORD AIRPORT       :   2  /  -18  /  0.00  / 0.0
DPA: DUPAGE AIRPORT         :   4  /  -14  /  0.00
UGN: WAUKEGAN AIRPORT       :   6  /  -13  /  0.00
ARR: AURORA/SUGAR GROVE     :   3  /  -14  /  0.00
PWK: WHEELING/CHI EXEC      :   8  /  -11  /  0.00
VPZ: VALPARAISO IN          :   8  /  -15  /  0.00
:
UNOFFICIAL SUPPLEMENTAL AWOS LOCATIONS
:
DKB: DEKALB                 :   2  /  -14  /
JOT: JOLIET                 :   7  /  -15  /
IKK: KANKAKEE               :   9  /  -12  /
IGQ: LANSING                :  10  /  -12  /
C09: MORRIS                 :   6  /  -12  /
VYS: PERU                   :   6  /  -10  /
PNT: PONTIAC                :  32  /  -6  /
RZL: RENSSELAER IN          :  16  /  -13  /
RPJ: ROCHELLE               :   3  /  -16  /
:
ADDITIONAL SUPPLEMENTAL AUTOMATED LOCATIONS
:
.END

THE FOLLOWING DATA PROVIDED BY NATIONAL WEATHER SERVICE COOPERATIVE
OBSERVERS. 24 HR TEMPERATURES AND PRECIPITATION ENDING AT INDICATED
TIME THIS MORNING. LOCATIONS ARE GROUPED BY CLIMATIC DIVISION.

.BR LOT 0128 C DH07/TAIRZX/TAIRZN/PPDRZZ/SFDRZZ/SDIRZZ

:                                                  SNOW  SNOW
:LOCATION               DATE/TIME  MAX  MIN  PCPN  FALL  DEPTH
:NORTHEAST ILLINOIS...
ARRI2: AURORA         :   DH0700/  -3 / -13 / 0.00 /  0.0/    8
BARI2: BARRINGTON 3SW :   DH0800/  -4 / -16 / 0.00 /     /   13
CBGI2: BOTANIC GARDENS:   DH0800/   0 / -13 / 0.00 /  0.0/   12
MFWI2: MIDWAY COOP    :   DH0700/   0 / -11 / 0.00 /  0.0/    6
DEKI2: DEKALB         :   DH0700/   0 / -14 / 0.00 /  0.0/    8
ELGI2: ELGIN          :   DH0700/  -2 / -14 / 0.00 /  0.0/    2
JOLI2: JOLIET LOCK/DAM:   DH0600/  -2 / -13 / 0.00 /  0.0/    2
MARI2: MARENGO        :   DH0700/  -4 / -19 / 0.00 /     /    9
MMOI2: MARSEILLES     :   DH0800/  -1 / -16 / 0.00 /  0.0/    3
MHYI2: MCHENRY        :   DH0800/  -5 / -17 / 0.00 /  0.0/    9
MOSI2: MORRIS         :   DH0800/  -1 / -12 / 0.00 /  0.0/    1
MUNI2: MUNDELEIN      :   DH0700/  -4 / -16 / 0.00 /  0.0/    5
OTTI2: OTTAWA 4SW     :   DH0745/   0 / -12 / 0.00 /     /    6
PKFI2: PARK FOREST    :   DH0600/   0 / -13 / 0.00 /  0.0/    2
:                                                  SNOW  SNOW
:LOCATION               DATE/TIME  MAX  MIN  PCPN  FALL  DEPTH
:NORTHWEST ILLINOIS...
PAWI2: PAW PAW        :   DH0700/  -4 / -14 / 0.00 /  0.0/    8
RCHI2: ROCHELLE       :   DH0600/  -4 / -16 / 0.00 /  0.0/    0
:                                                  SNOW  SNOW
:LOCATION               DATE/TIME  MAX  MIN  PCPN  FALL  DEPTH
:NORTHWEST INDIANA...
RZZI3: RENSSELAER     :   DH0730/   5 / -5 / 0.00 /  0.0/    6
VPOI3: VALPARAISO 5NNE:   DH0700/   2 / -14 /    T /    T/    8
:                                                  SNOW  SNOW
:LOCATION               DATE/TIME  MAX  MIN  PCPN  FALL  DEPTH
:EASTERN ILLINOIS...
CWWI2: DWIGHT         :   DH0700/  -1 / -12 / 0.00 /     /    6
KKEI2: KANKAKEE       :   DH0700/   0 / -12 / 0.00 /  0.0/    7
PXNI2: PAXTON         :   DH0700/   8 / -3 / 0.00 /     /    1
WATI2: WATSEKA        :   DH0700/   1 / -10 / 0.00 /  0.0/
.END
OTHER ADDITIONAL SUPPLEMENTARY REPORTS
                                                   SNOW  SNOW
:LOCATION               DATE/TIME  MAX  MIN  PCPN  FALL  DEPTH
BATI2: BATAVIA        :   DH0600/  -3 / -14 / 0.00 /  0.0/    7
CTYI2: COAL CITY 4NNW :   DH0600/   0 / -16 / 0.00 /  0.0/    5

THESE DATA ARE PRELIMINARY AND HAVE NOT UNDERGONE FINAL QUALITY
CONTROL BY THE NATIONAL CLIMATIC DATA CENTER /NCDC/.  THEREFORE...
THESE DATA ARE SUBJECT TO REVISION. FINAL AND CERTIFIED CLIMATE DATA
CAN BE ACCESSED AT WWW.NCDC.NOAA.GOV.

Lowest Wind Chills

January 28th Morning:

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE CHICAGO IL
929 AM CST TUE JAN 28 2014 /1029 AM EST TUE JAN 28 2014/

...LOWEST WIND CHILLS FROM MONDAY NIGHT AND TUESDAY...

OBSERVATIONS ARE COLLECTED FROM A VARIETY OF SOURCES WITH VARYING
EQUIPMENT AND EXPOSURE. NOT ALL DATA LISTED ARE CONSIDERED OFFICIAL.

LOCATION                            TEMP      TIME/DATE
---------------------------------------------------------
2 SSE STEWARD                     -35       0530 AM 01/28
DE KALB                           -34       0255 AM 01/28
ROCHELLE                          -34       0455 AM 01/28
ROMEOVILLE                        -31       0535 AM 01/28
VALPARAISO                        -31       0753 AM 01/28
AURORA AIRPORT /SUGAR GROVE/      -31       0152 AM 01/28
CHICAGO DOWNTOWN /NORTHERLY IS/   -30       0600 AM 01/28
MORRIS                            -30       0655 AM 01/28
CHICAGO OHARE AIRPORT             -30       0651 AM 01/28
DUPAGE AIRPORT                    -30       0952 PM 01/27
LANSING                           -29       0555 AM 01/28
RENSSELAER                        -29       0515 AM 01/28
ROCKFORD                          -28       1100 PM 01/27
KANKAKEE                          -28       0735 AM 01/28
CHICAGO MIDWAY AIRPORT            -28       0651 AM 01/28
JOLIET                            -27       0515 AM 01/28
WAUKEGAN                          -27       0652 AM 01/28
PERU                              -26       0555 AM 01/28
WHEELING                          -26       0652 AM 01/28

$$

January 27th Morning:

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE CHICAGO IL
958 AM CST MON JAN 27 2014 /1058 AM EST MON JAN 27 2014/

...LOWEST WIND CHILLS THROUGH 930 AM JANUARY 27TH...

OBSERVATIONS ARE COLLECTED FROM A VARIETY OF SOURCES WITH VARYING
EQUIPMENT AND EXPOSURE. NOT ALL DATA LISTED ARE CONSIDERED OFFICIAL.

LOCATION                       TEMP      TIME/DATE
------------------------------------------------------
DE KALB                        -33       0915 AM 01/27
2 SSE STEWARD                  -33       0830 AM 01/27
ROCKFORD                       -28       0854 AM 01/27
ROCHELLE                       -28       0855 AM 01/27
DUPAGE AIRPORT                 -28       0752 AM 01/27
AURORA AIRPORT /SUGAR GROVE/   -28       0905 AM 01/27
MORRIS                         -27       0835 AM 01/27
ROMEOVILLE                     -27       0815 AM 01/27
PERU                           -26       0935 AM 01/27
CHICAGO OHARE AIRPORT          -26       0851 AM 01/27
KANKAKEE                       -25       0815 AM 01/27
PONTIAC                        -25       0755 AM 01/27
VALPARAISO                     -25       0853 AM 01/27
JOLIET                         -24       0755 AM 01/27
PAXTON                         -24       0632 AM 01/27
CHICAGO MIDWAY AIRPORT         -24       0851 AM 01/27
LANSING                        -23       0935 AM 01/27
WHEELING                       -23       0934 AM 01/27
GARY                           -22       0745 AM 01/27
RENSSELAER                     -20       0515 AM 01/27

$$

MTF

Highest Wind Gusts From January 26th

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE CHICAGO IL
912 AM CST MON JAN 27 2014 /1012 AM EST MON JAN 27 2014/

...HIGHEST WIND GUSTS FROM THE NIGHT OF JANUARY 26TH...

THE FOLLOWING IS A LIST OF MAXIMUM WIND GUSTS...IN MPH...ALONG AND
IMMEDIATELY FOLLOWING THE ARCTIC COLD FRONT THAT MOVED THROUGH THE
REGION ON SUNDAY EVENING JANUARY 26TH.

OBSERVATIONS ARE COLLECTED FROM A VARIETY OF SOURCES WITH VARYING
EQUIPMENT AND EXPOSURE. NOT ALL DATA LISTED ARE CONSIDERED OFFICIAL.

LOCATION                       SPEED     TIME/DATE
------------------------------------------------------
PAXTON                         65        1117 PM 01/26
GARY                           58        0945 PM 01/26
2 SSE STEWARD                  58        1000 PM 01/26
1 SSW OTTAWA                   56        1000 PM 01/26
PONTIAC                        55        1015 PM 01/26
AURORA AIRPORT /SUGAR GROVE/   54        0811 PM 01/26
VALPARAISO                     53        1058 PM 01/26
ROCKFORD                       52        0716 PM 01/26
PERU                           52        0735 PM 01/26
ROCHELLE                       49        0735 PM 01/26
MORRIS                         48        1035 PM 01/26
ROMEOVILLE                     48        1035 PM 01/26
DE KALB                        48        1015 PM 01/26
DUPAGE AIRPORT                 47        1026 PM 01/26
LANSING                        45        0955 PM 01/26
RENSSELAER                     45        1015 PM 01/26
KANKAKEE                       44        1135 PM 01/26
CHICAGO OHARE AIRPORT          44        0818 PM 01/26
WHEELING                       43        0803 PM 01/26
CHICAGO MIDWAY AIRPORT         40        1027 PM 01/26
WAUKEGAN                       39        1213 AM 01/27
JOLIET                         36        1135 PM 01/26


$$

MTF

Snowfall Amounts from Sunday Evening, January 26th