|
Synopsis (courtesy of NWS Chicago) A very dynamic storm system impacted the area Wednesday night through Friday. This produced everything from some winter precipitation, to thunderstorms, dense fog, and even very strong winds across the area. The storm system first developed across the plains on Wednesday. Then, as the system progressed eastward Wednesday night, it induced a strengthening wind field a couple thousand feet off the ground. This is typically referred to by meteorologists as a low level jet. This low level jet pumped warmer and very moist air northward across the Mississippi Valley to the Lower Great Lakes region Wednesday night. As this moisture reached northern Illinois, strong convergence occurred along the northern periphery of the strongest southerly wind field late Wednesday night into Thursday. This is highlighted in the figure below. Ultimately, this continual moisture convergence across Northern Illinois led to the development of moderate to heavy precipitation across the area during the predawn hours of Thursday morning.
Most areas just received periods of moderate to heavy rain from this initial surge of moisture late Wednesday night. However, areas across far northern Illinois, especially areas north of interstate 88, were cold enough for the precipitation to begin as a period of wet snow, sleet and freezing rain. This resulted in a quick 1 to 2 inches of heavy wet snow accumulation early Thursday morning across far northern Illinois from this initial band of precipitation. Elsewhere across the area, thunderstorms with periods of heavy rain were the rule into Thursday morning. Then, during the afternoon Thursday, a surface warm front begin lifting northward across the area. With a much warmer and very moist airmass associated with this warm front, the combination of the melting snow and rapidly increasing low level moisture resulted in the development of very dense fog area-wide. This fog produced near-zero visibilities for a few hours Thursday afternoon.
During the late afternoon and early evening on Thursday, a line of showers and thunderstorms moved across the region ahead of an approaching strong cold front. These storms did not reach severe limits across northern Illinois or northwestern Indiana. However, our neighbors to the south across central Illinois did experience some severe gusty thunderstorms, with even a couple of tornados reported across west central Illinois.
Finally, as the surface low moved into southern Wisconsin early Thursday evening, it pushed a strong cold front across the area. In the wake of this front the winds increased significantly out of the southwest. Winds gusted between 50 to 65 mph for a period Thursday evening following this frontal passage. The wind magnitudes were so strong due to the fact that the surface low continued to strengthen rapidly as it was moving northward across Wisconsin. This resulted in a very strong pressure gradient as surface high pressure set up across the southern United States.
Below is a loop of the satellite water vapor imagery (similar to the figure above). The blue colder colors show areas of enhanced moisture in the atmosphere, such as that from clouds and precipitation, while the warmer colors indicated drier areas in the atmosphere. This information is useful to meteorologists as we track storm systems across the country in real time. Also shown is the location and track of the surface low. The green arrows are the moisture transport vectors approximately 3,500 feet above the ground. This shows us that significant moisture was rapidly being transported northward from the Gulf of Mexico. A large influx of deep moisture is an important ingredient in heavy precipitation. Note that the loop starts late Wednesday night and runs through late Wednesday afternoon.
**********************************************************************************************************************************************************************
|
||||||||||||||||||||||||
| Precipitation Maps | ||||||||||||||||||||||||
|
||||||||||||||||||||||||
| **************Table of Storm Reports************** | ||||||||||||||||||||||||
PRELIMINARY LOCAL STORM REPORT...SUMMARY NATIONAL WEATHER SERVICE QUAD CITIES IA IL 912 PM CST THU FEB 20 2014 ..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON... ..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE.... ..REMARKS.. 1219 PM HEAVY RAIN 2 SSE BURLINGTON 40.79N 91.11W 02/20/2014 M2.00 INCH DES MOINES IA TRAINED SPOTTER STORM TOTAL SO FAR. 1226 PM HAIL VICTOR 41.73N 92.29W 02/20/2014 E0.25 INCH IOWA IA TRAINED SPOTTER 0107 PM HAIL WASHINGTON 41.30N 91.69W 02/20/2014 M0.75 INCH WASHINGTON IA FIRE DEPT/RESCUE DIME SIZE HAIL LASTED 5 MINUTES. 0117 PM HAIL N RIVERSIDE 41.48N 91.57W 02/20/2014 M0.25 INCH WASHINGTON IA TRAINED SPOTTER 0122 PM HAIL HILLS 41.57N 91.54W 02/20/2014 M0.50 INCH JOHNSON IA TRAINED SPOTTER PEA TO DIME SIZE HAIL. LASTING 3 MIN. VIA ESPOTTER. 0135 PM HAIL MARION 42.03N 91.59W 02/20/2014 M1.00 INCH LINN IA LAW ENFORCEMENT INTERSECTION OF HWYS 13 AND 151 0153 PM HAIL W PLEASANT PLAIN 41.15N 91.86W 02/20/2014 E0.25 INCH JEFFERSON IA TRAINED SPOTTER 0200 PM HEAVY RAIN 3 ENE CHARLIE HEATH MEM 40.60N 91.84W 02/20/2014 M1.80 INCH CLARK MO TRAINED SPOTTER TOTAL. 0200 PM HAIL 1 E BRIGHTON 41.17N 91.80W 02/20/2014 M0.25 INCH WASHINGTON IA CO-OP OBSERVER LASTED 2 MIN. 0200 PM TSTM WND DMG IOWA CITY 41.66N 91.54W 02/20/2014 JOHNSON IA EMERGENCY MNGR FEW POWER LINES DOWN BENTON STREET 0202 PM HAIL S WELLMAN 41.47N 91.84W 02/20/2014 M0.25 INCH WASHINGTON IA TRAINED SPOTTER 0208 PM FLOOD FORT MADISON 40.62N 91.35W 02/20/2014 LEE IA TRAINED SPOTTER ROADWAYS BECOMING FLOODED. FLOODING IS OCCURRING AND PASSING UNDER DOORWAYS AND ENTERING HALLWAYS THROUGH FORT MADISON HIGH SCHOOL. HEAVY RAIN SUBSIDED BY 226PM. VIA ESPOTTER. 0213 PM SLEET 1 SSE CEDAR RAPIDS 41.95N 91.66W 02/20/2014 E0.00 INCH LINN IA TRAINED SPOTTER HEAVY SLEET FALLING. 0216 PM HAIL 5 NW IOWA CITY 41.71N 91.60W 02/20/2014 M0.25 INCH JOHNSON IA TRAINED SPOTTER HEAVY RAIN AND PEA SIZE HAIL LASTED 5 MIN. 0218 PM HAIL 1 E IOWA CITY 41.66N 91.51W 02/20/2014 M0.25 INCH JOHNSON IA TRAINED SPOTTER LASTED 2 MIN. 0219 PM HAIL 1 SSE CEDAR RAPIDS 41.95N 91.66W 02/20/2014 M0.25 INCH LINN IA TRAINED SPOTTER VIA ESPOTTER. 0222 PM HAIL 4 W CEDAR RAPIDS 41.96N 91.75W 02/20/2014 M0.25 INCH LINN IA TRAINED SPOTTER STRONG WINDS WITH HAIL. 0222 PM HAIL MARION 42.03N 91.59W 02/20/2014 M0.50 INCH LINN IA TRAINED SPOTTER PEA TO MARBLE SIZE FROM 1422 TO 1425. VIA ESPOTTER. 0222 PM HAIL FORT MADISON 40.62N 91.35W 02/20/2014 M0.50 INCH LEE IA TRAINED SPOTTER PEA TO DIME SIZE HAIL. SOME IN TOWN ROADS HAVE 1 FOOT OF WATER ON THEM. 0224 PM HAIL HIAWATHA 42.05N 91.68W 02/20/2014 M0.25 INCH LINN IA TRAINED SPOTTER NUMEROUS REPORTS OF PEA SIZE HAIL WITHIN A FEW MINUTES OF THIS REPORT TIME. 0224 PM HAIL 3 S CEDAR RAPIDS 41.92N 91.66W 02/20/2014 M0.25 INCH LINN IA TRAINED SPOTTER 0230 PM HAIL W BURLINGTON 40.81N 91.12W 02/20/2014 M0.25 INCH DES MOINES IA TRAINED SPOTTER LASTED FOR AROUND 5 MIN. 0235 PM HAIL 2 NNW MARION 42.06N 91.61W 02/20/2014 M0.25 INCH LINN IA TRAINED SPOTTER VIA FACEBOOK. 0250 PM TSTM WND GST 2 W LIME CITY 41.65N 91.12W 02/20/2014 M61.00 MPH CEDAR IA DEPT OF HIGHWAYS IADOT OBSERVATION 0302 PM FLOOD 1 ENE FORT MADISON 40.63N 91.33W 02/20/2014 LEE IA TRAINED SPOTTER FLOODING AT 12TH AND AVE H. 0306 PM HAIL SE MUSCATINE 41.41N 91.07W 02/20/2014 M0.25 INCH MUSCATINE IA TRAINED SPOTTER 0315 PM TSTM WND DMG 4 W MAQUOKETA 42.07N 90.74W 02/20/2014 JACKSON IA CO-OP OBSERVER 1/2 OF HOUSE SHINGLES WERE BLOWN OFF HOUSE. NOT SURE OF EXACT WIND SPEED. 0315 PM HAIL 4 W MAQUOKETA 42.07N 90.74W 02/20/2014 M0.25 INCH JACKSON IA CO-OP OBSERVER 1/8 TO 1/4 INCH HAIL. 0342 PM SLEET W BELLE PLAINE 41.90N 92.28W 02/20/2014 E0.00 INCH BENTON IA TRAINED SPOTTER 0352 PM HEAVY RAIN WASHINGTON 41.30N 91.69W 02/20/2014 M1.45 INCH WASHINGTON IA PUBLIC RELAYED VIA MEDIA. 0357 PM HEAVY RAIN 2 N NEW WINDSOR 41.23N 90.45W 02/20/2014 M1.31 INCH MERCER IL TRAINED SPOTTER TOTAL FOR LAST 18 HOURS. 0.62 INCH SINCE 700AM. VIA ESPOTTER. 0400 PM HEAVY RAIN PARK VIEW 41.69N 90.54W 02/20/2014 M1.16 INCH SCOTT IA NWS EMPLOYEE STORM TOTAL RAINFALL THROUGH 4 PM 0415 PM HAIL 4 ENE FREEPORT 42.32N 89.57W 02/20/2014 M0.25 INCH STEPHENSON IL TRAINED SPOTTER 1/4 TO 3/8 INCH HAIL. 0445 PM HEAVY RAIN 1 NW DAVENPORT 41.56N 90.61W 02/20/2014 M1.28 INCH SCOTT IA TRAINED SPOTTER TOTAL. 0500 PM HEAVY RAIN MARION 42.03N 91.59W 02/20/2014 M0.71 INCH LINN IA CO-OP OBSERVER 24HR TOTAL AT COOP SITE. SNOW DEPTH IS 11 INCHES. 0500 PM HEAVY RAIN HENNEPIN 41.26N 89.32W 02/20/2014 M1.91 INCH PUTNAM IL CO-OP OBSERVER 24HR TOTAL. 0550 PM HEAVY RAIN 1 WSW BROCK 40.55N 92.17W 02/20/2014 M1.60 INCH SCOTLAND MO TRAINED SPOTTER TOTAL. 0600 PM HEAVY RAIN DONNELLSON 40.64N 91.56W 02/20/2014 M2.21 INCH LEE IA CO-OP OBSERVER STORM TOTAL OF 24 HOUR EVENT RAINFALL 0600 PM HEAVY RAIN AUGUSTA 40.75N 91.28W 02/20/2014 M2.40 INCH LEE IA CO-OP OBSERVER 24HR PERIOD. 0600 PM HEAVY RAIN MOLINE QUAD-CITY AIRPOR 41.45N 90.50W 02/20/2014 M1.30 INCH ROCK ISLAND IL OFFICIAL NWS OBS 24HR TOTAL. 0600 PM HEAVY RAIN DAVENPORT MUNICIPAL AIR 41.62N 90.58W 02/20/2014 M1.14 INCH SCOTT IA OFFICIAL NWS OBS 24HR TOTAL. 0600 PM HEAVY RAIN IOWA CITY MUNICIPAL AIR 41.63N 91.55W 02/20/2014 M0.76 INCH JOHNSON IA ASOS 24HR TOTAL. 0600 PM HEAVY RAIN DUBUQUE REGIONAL AIRPOR 42.40N 90.72W 02/20/2014 M0.49 INCH DUBUQUE IA ASOS 24HR TOTAL. 0600 PM HEAVY RAIN CEDAR RAPIDS MUNICIPAL 41.88N 91.72W 02/20/2014 M0.66 INCH LINN IA ASOS 24HR TOTAL. 0600 PM HEAVY RAIN BURLINGTON REGIONAL AIR 40.78N 91.13W 02/20/2014 M1.84 INCH DES MOINES IA ASOS 24HR TOTAL. 0851 PM HEAVY RAIN W CANTRIL 40.64N 92.07W 02/20/2014 M1.28 INCH VAN BUREN IA TRAINED SPOTTER TOTAL. && THE REPORTS BELOW ARE SEPARATED INTO SNOW...AND ICE AND SLEET CATEGORIES...THEN BY AMOUNT...AND ARE NOT NECESSARILY THE FINAL AMOUNT FOR EACH LOCATION. SLEET AND FREEZING RAIN REPORTS LISTED BY AMOUNT INCHES LOCATION ST COUNTY TIME ------ ----------------------- -- -------------- ------- 0.0 W BELLE PLAINE IA BENTON 0342 PM 0.0 1 SSE CEDAR RAPIDS IA LINN 0213 PM |
||||||||||||||||||||||||
Follow us on Twitter
Follow us on Facebook
Follow us on YouTube
DVN RSS Feed