Recently in PAUL DAILEY Category

By Meteorologist Paul Dailey

Meteorological winter is two-thirds over in Chicago, and at this point the winter of 2011-12 stands as the warmest since 1931-32 and the ninth warmest overall dating back to 1871. January ended with overall temperatures averaging 6 degrees above normal as a cool front approached from the west Tuesday afternoon. Southwesterly winds gusting to 30 mph pushed the official high at O'Hare International Airport to 57 degrees, tying Dec. 15 for the highest reading since the Dec. 1 start of meteorological winter. Midway Airport and Northerly Island both recorded highs of 58, and the mildest area reading was 61 degrees at Pontiac.

Storm brewing
While Chicago weather continues to be relatively mild, a major winter storm is brewing in the central Plains. Intensifying low pressure in Kansas will slam moisture-laden air from the Gulf of Mexico against the foothills of western Kansas and Nebraska and the foothills and mountains of eastern Colorado, dumping a foot or more of snow. Blinding snow driven by strong east to northeast winds will likely create blizzard conditions in that area later Thursday into Friday.
Current computer models have the center of that storm moving east up the Ohio River Valley. Under that scenario, Chicago will rest on the northern edge of the storm and receive a light rain-snow mix over the weekend. Any jog in the storm track could impact the amount and type of precipitation that falls across the area. It's a development worth monitoring in coming days. Stay tuned.

By Meteorologist Paul Dailey

As central Plains low pressure approached from the southwest Sunday evening a Tornado watch was issued by the National Storm Prediction Center for portions of southern Illinois south into Arkansas. By 8 PM CDT severe thunderstorms and tornadoes broke out across eastern Arkansas and a solid line of northeastward-moving potentially severe thunderstorms extended north into southern Illinois. As the center of low pressure tracked east and north of Chicago Sunday night, showers and even a few thunderstorms were expected to spread into northeast Illinois, northwest Indiana and even southeastern Wisconsin---eating away at the fresh snow cover.

Colder air Monday
Strong west winds gusting to 40 mph will usher colder air into the metro area Monday forenoon with rain changing-over to wet snow. Flurries will end as clouds move out later Monday. Temperatures will still be above normal for the rest of the workweek with an upper air jet stream shift pulling colder air into the area again next weekend.

 

Low pressure developing in the central Plains will move northeast toward Lake Michigan today and pass over the Lake later tonight and early Monday with a widespread display of significant weather expected to develop in advance of the system. A strong upper air trough is swinging east out of the southwestern U.S. creating added support and additional instability to the central Plains system.

 

Chicago will rest in the cooler air under an extensive cloud cover north of the warm front which will be situated along the Ohio River Valley. Strong southerly winds just a few thousand feet above the surface will overrun the warm front with widespread cloudiness extending far to the north into the western Great Lakes. This cloud deck will keep ground-level temperatures in central and northern Illinois and Indiana close to or just below 32 degrees into the afternoon - and as the clouds thicken, drizzle or very light rain could develop which in turn could create some slick spots on untreated sidewalks and roadways.

 

Later this afternoon and tonight, as the storm system and associated cold front approaches, vertical motion is expected to enhance convective storm development over the lower Mississippi and Ohio Valley - with potentially severe storms moving into southern and central Illinois and Indiana - possibly as far north as the area just south of Chicago and northern Indiana. Rainfall over the Chicago area could eliminate much of the freshly-fallen snow cover tonight - which in turn could create significant rapid runoff of more than an inch moisture and subsequent flooding problems on some of the local streams and in low-lying flood-prone areas.

 

There will be an area of heavy snow with this storm system, but it will most likely occur to the north of the center of low pressure - over and north of Lake Superior and northern Minnesota.

By Meteorologist Paul Dailey

As a center of low pressure develops in the central Plains and moves northeast toward Lake Michigan, clouds will spread over the Chicago area Sunday. Temperatures may be very close or just below 32-degrees early Sunday, and any drizzle could freeze on contact with cold surfaces, creating slick spots. especially on sidewalks and overpasses. However as the day progresses, temperatures will quickly rise above freezing. As the center of low pressure tracks north of Chicago, the associated cold front will sweep through the Chicago area early Monday with strong west winds ushering in colder air and rain changing over to snow flurries.

With the upper level jet stream flowing west to east across the northern U.S., the arctic air will be held far to the north across central and northern Canada, and Chicago will be in line of air masses originating over the northern Pacific. Northern Illinois temperatures for the next week to 10 days are projected to average above normal.

 

As low pressure spreads snow from the central plains east into the Midwest this morning, the National Weather Service has issued a combination of Winter Storm Warnings and Winter Weather Advisories for the next 24 to 36 hours extending from extreme southeastern South Dakota through southern Minnesota, much of Iowa, southern and northern Wisconsin, northern Illinois, southern Lower Michigan, northern and central Indiana, and all of Ohio, Pennsylvania into New Jersey. Snowfall amounts will range from 3 to 8 inches along this west-east path as a low pressure system tracks out of the central plains east up the Ohio Valley Friday into Saturday. Where temperatures are closer to 32 degrees, portions of Ohio and Pennsylvania will experience a mix of freezing rain and sleet along with eventual snow accumulation.

 

In the Chicago area including southeast Wisconsin and northwest Indiana anywhere from 3 to 8 inches of snow could occur with Chicago itself positioned to possibly be hit with greatest amounts in the 5 to 8-inch range due to the initial storm surge into this evening - followed by a northeast wind on the backside of the low pressure system as it moves to the east possibly creating lake effect snow along the Illinois Lake Michigan shoreline later tonight into Saturday.

 

A WINTER WEATHER ADVISORY IS IN EFFECT FOR THE FOLLOWING COUNTIES AND CITIES IN NORTHEAST ILLINOIS AND NORTHWEST INDIANA....
LA SALLE-GRUNDY-KANKAKEE-NEWTON-JASPER-BENTON-
INCLUDING THE CITIES OF...OTTAWA...MORRIS...KANKAKEE...MOROCCO...
RENSSELAER...FOWLER

...WINTER WEATHER ADVISORY IN EFFECT FROM 9 AM CST /10 AM EST/
THIS MORNING TO MIDNIGHT CST /1 AM EST/ TONIGHT...

THE NATIONAL WEATHER SERVICE IN CHICAGO HAS ISSUED A WINTER
WEATHER ADVISORY FOR SNOW...WHICH IS IN EFFECT FROM 9 AM CST /10
AM EST/ THIS MORNING TO MIDNIGHT CST /1 AM EST/ TONIGHT.

* TIMING...SNOW WILL DEVELOP DURING THE MID TO LATE MORNING HOURS
  AND CONTINUE THROUGH THIS AFTERNOON...THEN ENDING TONIGHT. THE
  HEAVIEST SNOWFALL WILL OCCUR THIS AFTERNOON.

* ACCUMULATIONS...SNOWFALL TOTALS OF 3 TO 6 INCHES CAN BE
  EXPECTED WITH LOCALLY HEAVIER TOTALS POSSIBLE.

* HAZARDS...SNOW COULD FALL RATHER HEAVILY AT TIMES RESULTING IN
  REDUCED VISIBILITIES AND SNOWFALL RATES OF A HALF INCH TO INCH
  PER HOUR AT TIMES.

* IMPACTS...ACCUMULATING SNOW WILL CAUSE SIGNIFICANTLY INCREASED
  TRAVEL TIMES...RESULTING IN A PARTICULARLY TREACHEROUS COMMUTE
  THIS AFTERNOON. IN ADDITION...VERY COLD TEMPERATURES IN THE
  TEENS WILL MAKE SALT LESS EFFECTIVE MAKING IT HARDER FOR ROAD
  CREWS TO KEEP ROADS CLEAR OF SNOW AND ICE. THE SNOW WILL ALSO
  RESULT IN SIGNIFICANT DISRUPTIONS TO AIR TRAVEL AS WELL.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY FOR SNOW MEANS THAT PERIODS OF SNOW
WILL CAUSE PRIMARILY TRAVEL DIFFICULTIES. BE PREPARED FOR SNOW
COVERED ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE
DRIVING.

 

WINTER STORM WARNING FOR THE FOLLOWING COUNTIES
WINNEBAGO-BOONE-OGLE-DE KALB-MCHENRY-LAKE-KANE-DUPAGE-COOK
INCLUDING THE CITIES OF...ROCKFORD...BELVIDERE...OREGON...DEKALB...WAUKEGAN...WOODSTOCK...AURORA AND WHEATON AND CHICAGO 

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL 9 PM CST THIS
EVENING.

* TIMING...SNOW WILL DEVELOP DURING THE EARLY TO MID MORNING HOURS IN WESTERN PORTIONS AND CONTINUE THROUGH THIS AFTERNOON...ENDING THIS EVENING. THE HEAVIEST SNOWFALL WILL OCCUR DURING THE LATE MORNING INTO THE MID AFTERNOON.

* ACCUMULATIONS...SNOWFALL TOTALS OF 5 TO 8 INCHES CAN BE
  EXPECTED.

* HAZARDS...SNOW WILL FALL HEAVILY AT TIMES RESULTING IN REDUCED
  VISIBILITIES AND SNOWFALL RATES OF AROUND ONE INCH PER HOUR AT
  TIMES.

* IMPACTS...ACCUMULATING SNOW WILL CAUSE SIGNIFICANTLY INCREASED
  TRAVEL TIMES...RESULTING IN A PARTICULARLY TREACHEROUS AFTERNOON
  COMMUTE. IN ADDITION...VERY COLD TEMPERATURES IN THE TEENS WILL
  MAKE SALT LESS EFFECTIVE AND COMBINE WITH HEAVY SNOWFALL RATES
  TO MAKE IT HARDER FOR ROAD CREWS TO KEEP ROADS CLEAR OF SNOW AND
  ICE. THE SNOW WILL ALSO RESULT IN SIGNIFICANT DISRUPTIONS TO AIR
  TRAVEL AS WELL.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING FOR HEAVY SNOW MEANS SEVERE WINTER WEATHER
CONDITIONS ARE EXPECTED OR OCCURRING. SIGNIFICANT AMOUNTS OF SNOW
ARE FORECAST THAT WILL MAKE TRAVEL DANGEROUS. ONLY TRAVEL IN AN
EMERGENCY. IF YOU MUST TRAVEL...KEEP AN EXTRA FLASHLIGHT...
FOOD...AND WATER IN YOUR VEHICLE IN CASE OF AN EMERGENCY.

By Meteorologist Paul Dailey

Accumulating snow is forecast to begin falling mid-to-late morning Friday -- spreading from the west in advance of a low pressure system expected to move through southern Illinois in the afternoon and up the Ohio River Valley on Friday night. Heaviest snowfall rates in the Chicago area should peak at a half-inch to 1-inch per hour in the middle and late afternoon Friday. Snow is expected to diminish overnight as the low pressure moves east.

The chain of low pressure disturbances continues to batter the Pacific Northwest with copious rainfall and heavy snow before moving inland over the Rockies and into the Plains and Midwest in about 48-hour intervals. The next low pressure disturbance in this series to impact the Chicago area should approach early Sunday, bringing rain changing to snow before ending Sunday night. After that, the next low pressure impulse could bring rain or snow Wednesday.