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McHenry County, IL Weather and Climate Synopsis

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Weather Summary Hourly Observations Nowcast Agricultural Weather Outlook
7 Day Forecast Medium & Long Range Outlook Almanac Historical Facts

US Weekly Rainfall Departure

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A joint service of the UK Ag Weather Center and the National Weather Service.

Weather Summary For Central And Southeast Illinois
National Weather Service Lincoln IL
704 PM CDT Wed Mar 21 2018

High pressure built into the central U.S. on Wednesday, providing
sunny skies and cool air to central and southeast Illinois. High
temperatures reached the middle to upper 40s.

A fast moving disturbance will track southeast from Iowa into
southern Illinois on Thursday, bringing a chance for scattered
rain showers. A larger storm system will begin to impact the
Midwest on Friday, and linger into Saturday. Strong low pressure
will spread rain and snow across the region. Several inches of
snow accumulation is possible from northeast Iowa, southeast into
portions of northern Illinois, and Indiana, for Friday night and 
Saturday. Farther south, rain totals in excess of one inch are 
possible, for central and southern Illinois.

Low temperatures tonight will drop into the mid 20s to mid 30s
across the Midwest. Highs on Thursday will range from the mid 40s
in northern Indiana, to the lower 60s in central Missouri.

National Ag. Weather Outlook, International Ag. Weather Summary
Current Surface Map, [2nd Source TWC]

Click here for UKAWC Point Agricultural, Lawn & Garden Forecast/Outlook in case of corrupt tables.
Regional Hourly Observations For MCHENRY County
Issued at 1100 PM CDT WED MAR 21 2018

CHICAGO-OHARE  FAIR      30  21  69 N5        30.23S WCI  25          
CHICAGO-MIDWAY FAIR      32  23  69 N8        30.24R WCI  25          
AURORA         FAIR      28  20  71 E3        30.24R                  
LANSING*       FAIR      31  25  81 CALM      30.24R                  
JOLIET*        FAIR      29  21  73 CALM      30.25R                  
WAUKEGAN       FAIR      25  19  78 NW3       30.23R                  
DUPAGE AIRPORT FAIR      26  21  81 NE3       30.23R                  
KANKAKEE*      FAIR      29  19  66 CALM      30.26R                  
WHEELING       FAIR      29  21  72 CALM      30.25S                  
MORRIS*        FAIR      29  18  62 CALM      30.24R                  
ROMEOVILLE*    FAIR      28  23  81 NE8       30.24S WCI  20          
NORTHERLY ISL    N/A     32  23  70 N9          N/A  WCI  24          

Current Temperatures, Dewpoint Map, RH, Wind, Regional Obs, Surface 4-Panel
Meteograms : Springfield , Peoria , Quad City , Chicago (O'Hare) , Rockford

Current Agricultural Weather Conditions in Illinois
Based on observations at 1100pm CDT, Wednesday March 21, 2018

Across Illinois...temperatures are near 30 degrees north, near 36 degrees central, and near 27 degrees south. Current sky conditions are fair north, fair central, and fair south. In the north, relative humidity is near 60%, and the dew point is near 18 degrees. In the central part of the state, relative humidity is near 52%, and the dew point is near 20 degrees. In the south, relative humidity is near 89%, and the dew point is near 24 degrees. Winds are from the southeast at 7 mph north, where conditions are favorable for spraying. The wind chill is near 23 degrees north. Winds are from the northwest at 3 mph central, where conditions are favorable for spraying. Winds are calm south, where conditions are favorable for spraying. Based on current available observations, the highest temperature is 38 degrees at Sparta. The lowest temperature is 25 degrees at Waukegan, Rochelle, and Pontiac.

Current NOWCAST not available:
Nowcasts are not issued routinely during fair weather. Only when
precipitation or other significant weather is occuring in this county will these
forecasts be issued. Currently, there is no short term forecast in effect.

US Radar, All NWS Radars (In near-real time),Livestock Heat Stress Index (LSI), Wind Chill Map
Hazardous Weather Outlook For MCHENRY County,IL

347 PM CDT Wed Mar 21 2018 /447 PM EDT Wed Mar 21 2018/

 DAY ONE  Tonight.

Flooding is expected along portions of the Kankakee River.

 DAYS TWO THROUGH SEVEN  Thursday through Tuesday.

Friday and Saturday  
  Elevated Ice Accumulation Risk.
  Elevated Snow and Sleet Risk.


A winter storm will impact the region Friday night into Saturday.
Minor accumulations will be possible for much of the area but
there is the potential for a narrow corridor of heavy snowfall.
In addition, some areas near and south of the Illinois River and 
Kankakee River valleys will experience a wintry mix with the 
potential for some minor icy accumulations.

Portions of the Kankakee River will remain in flood.


Spotter activation will not be necessary through tonight.

NWS Severe Weather Map , Convective Outlook

7-Day Forecast For MCHENRY County, IL
300 PM CDT Wed Mar 21 2018

Clear. Lows in the lower 20s. Northeast winds around 5 mph in the evening shifting to the northwest after midnight.

Mostly sunny. Highs in the upper 40s. Northwest winds 5 to 10 mph.

Mostly clear. Lows in the mid 20s. Northeast winds 5 to 10 mph.

Mostly sunny in the morning then becoming partly cloudy. Highs in the mid 40s. East winds 10 to 15 mph.

Mostly cloudy. Chance of light snow in the evening, then light snow likely after midnight. Some snow accumulation possible. Lows in the upper 20s. East winds 10 to 15 mph. Chance of precipitation 70 percent.

Mostly cloudy. Light snow in the morning, then a chance of light snow in the afternoon. Some snow accumulation possible. Highs in the mid 30s. Chance of precipitation 80 percent.

Partly cloudy in the evening then clearing. Lows in the mid 20s.

Mostly sunny. Highs in the lower 40s.

Partly cloudy. Lows in the upper 20s.

Partly sunny. Highs in the upper 40s.

Mostly cloudy. Chance of rain in the evening, then rain likely after midnight. Lows in the upper 30s. Chance of precipitation 60 percent.

Cloudy with rain. Highs in the lower 50s. Chance of precipitation 80 percent.

Mostly cloudy. A 40 percent chance of rain in the evening. Lows in the mid 30s.

Mostly cloudy. Highs around 50.

12-48 Hr Surface, 12-48 Hr ETA 500mb/Sfc, TWC Forecast, Fire Danger, Day 1 Precip, Day 2 Precip, Days 1-5 Precip
NGM 60 Hr Forecast Meteograms : Springfield , Peoria , Quad City , Chicago (O'Hare) , Rockford , Severe Weather Pot.-Day 1, Day 2

Medium & Long Range Outlook For Illinois
                 6 TO 10 DAY  8 TO 14 DAY   30 DAY    90 DAY 
               MAR 27-MAR 31 MAR 29-APR 4    MAR       MAR-MAY                      
                 -----------  -----------  --------  ---------
   Temperature:      Above        Below      Below     Normal                      
 Precipitation:      Above       Normal     Normal      Above                      

....  Medium and long range outlooks provided by NCEP/K. Thomas Priddy
5 Day Rainfall Forecast, 6 to 10 Day , 8 to 14 Day , Text, 30-Day Outook, 90-Day Outook, 120-Day Outlook
MRF 10-Day Forecast Meteograms : Springfield , Peoria , Quad City , Chicago (O'Hare) , Rockford

Almanac Information

Thursday March 22, 2018 the 81th Day of Year

Declination 1.020000
Distance 0.999721 AU
Rise 06:58 EDT Set 19:14 EDT
Transit Meridian 13:05 EDT
Civil Twilight Begins 06:32 EDT Ends 19:40 EDT

Calculations made for central point in the state.
Time in ET -- and will vary due to location and
elevation -- Priddy

Historical Weather And Climate Facts For Today

A spectactular display of the Northern Lights was visible as far south as
Bradenton FL, El Paso TX, and Fresno CA. At Detroit MI, the display was
described "so brilliant as to blot out all stars below first magnitude".
(22nd-23rd) (The Weather Channel)
A great flood crested on rivers from Ohio to Maine. The flood claimed 107
lives and caused 270 million dollars property damage. (David Ludlum)
Six to ten inch rains caused the Chicago River to overflow its banks. (The
Weather Channel)

Ag Weather Center, Department of Biosystems & Agricultural Engineering, University of Kentucky