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McHenry County, IL Weather and Climate Synopsis

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36 Hr. Forecast Map
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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

US Weekly Temperature 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
1112 AM CDT Sun May 27 2018

Sunny skies were seen across central and southeast Illinois, 
through the late morning hours. Temperatures around the area 
at 11 a.m., ranged from the middle to upper 80s.

A weak frontal boundary stretching across the Midwest will slowly
push southeastward, bringing isolated storms to portions of the 
region today. After that, hot and mainly dry weather will be on 
tap across the entire region through the remainder of the Memorial
Day holiday weekend.

High temperatures today, will top out in the lower to middle 90s 
across the Midwest.

Overnight low temperatures, will range from near 60 degrees across
northern Wisconsin, to the lower 70s across the Missouri bootheel.

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 1200 PM CDT SUN MAY 27 2018

CHICAGO-OHARE  FAIR      91  62  37 S5        29.87R HX  91           
CHICAGO-MIDWAY FAIR      91  64  40 VRB3      29.87R HX  92           
AURORA         FAIR      91  64  40 CALM      29.88S HX  92           
LANSING*       FAIR      90  69  50 SW3       29.88S HX  94           
JOLIET*        FAIR      91  69  49 S3        29.88S HX  95           
WAUKEGAN       FAIR      90  59  35 CALM      29.87R HX  89           
DUPAGE AIRPORT FAIR      90  65  43 S6        29.88R HX  92           
KANKAKEE*      FAIR      92  65  41 SW7       29.89S HX  93           
WHEELING       FAIR      93  60  33 CALM      29.89R HX  93           
MORRIS*        FAIR      92  60  33 W5        29.87R HX  92           
ROMEOVILLE*    FAIR      90  64  41 W5        29.88S HX  91           

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 1200pm CDT, Sunday May 27, 2018

Across Illinois...temperatures are near 90 degrees north, near 90 degrees central, and near 89 degrees south. Current sky conditions are fair north, fair central, and fair south. In the north, relative humidity is near 42%, and the dew point is near 64 degrees. The heat index is near 91 degrees north. In the central part of the state, relative humidity is near 53%, and the dew point is near 71 degrees. The heat index is near 96 degrees central. In the south, relative humidity is near 60%, and the dew point is near 74 degrees. The heat index is near 98 degrees south. The livestock heat stress category is danger north, danger central, and danger south. Winds are from the southwest at 5 mph north, where conditions are favorable for spraying. Winds are from the south at 10 mph central, where conditions are favorable for spraying. Winds are from the south at 5 mph south, where conditions are favorable for spraying. Based on current available observations, the highest temperature is 94 degrees at Peru. The lowest temperature is 80 degrees at Fairfield.

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

351 AM CDT Sun May 27 2018 /451 AM EDT Sun May 27 2018/

 DAY ONE  Today and Tonight.

  Limited Thunderstorm Risk.
  Limited Excessive Heat Risk.


Early season heat will result in maximum heat index values in the
mid to upper 90s today. Isolated thunderstorms are possible west 
of a McHenry to Pontiac, Illinois this afternoon. Severe storms 
are not expected.

 DAYS TWO THROUGH SEVEN  Monday through Saturday.

  Limited Excessive Heat Risk.
Wednesday through Saturday  
  Limited Thunderstorm Risk.


Maximum heat index values are forecast to once again be in the 
mid to upper 90s Memorial Day Monday away from the lake. 


Spotter activation will not be necessary through tonight.


Moving from the northwest to southeast at 20 MPH.

NWS Severe Weather Map , Convective Outlook

7-Day Forecast For MCHENRY County, IL
1138 AM CDT Sun May 27 2018

Mostly sunny. A 20 percent chance of showers and thunderstorms in the afternoon. Highs in the mid 90s. Southwest winds 5 to 10 mph.

Clear. Lows in the upper 60s. South winds around 5 mph.

Sunny. Highs in the mid 90s. Northwest winds around 5 mph in the morning shifting to the southeast in the afternoon.

Mostly clear. Lows in the mid 60s. East winds around 5 mph.

Mostly sunny in the morning then becoming partly cloudy. Highs around 90. East winds 5 to 10 mph.

Partly cloudy. Lows in the mid 60s.

Mostly cloudy. Chance of showers and a slight chance of thunderstorms in the morning, then showers likely and a chance of thunderstorms in the afternoon. Highs around 80. Chance of precipitation 60 percent.

Mostly cloudy. A 40 percent chance of showers and thunderstorms in the evening. Lows in the lower 60s.

Partly cloudy. Highs in the lower 80s. Lows near 60.

Mostly sunny. Highs in the upper 70s.

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 
                 JUN 1-JUN 5  JUN 3-JUN 9    MAY       MAY-JUL                      
                 -----------  -----------  --------  ---------
   Temperature:      Above       Normal      Above      Above                      
 Precipitation:      Below        Below     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

Sunday May 27, 2018 the 147th Day of Year

Declination 21.460000
Distance 0.999716 AU
Rise 06:35 EDT Set 21:18 EDT
Transit Meridian 13:56 EDT
Civil Twilight Begins 06:05 EDT Ends 21:48 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 massive tornado struck Saint Louis MO killing 306 persons and causing
thirteen million dollars damage. The tornado path was short, but cut across
a densely populated area. It touched down six miles west of Eads Bridge in
Saint Louis and widened to a mile as it crossed into East Saint Louis. The
tornado was the most destructive of record in the U.S. up until that time.
It pierced a five-eighths inch thick iron sheet with a two by four inch
pine plank. A brilliant display of lightning accompanied the storm. (David
Ludlum) (The Weather Channel)

A tornado struck Louisville, with terrific lightning. (NWS Louisville)

Severe thunderstorms in West Texas produced baseball size hail at Crane,
hail up to three and a half inches in diameter at Post, and grapefruit size
hail south of Midland. Five days of flooding commenced in Oklahoma.
Thunderstorms produced 7 to 9 inches of rain in central Oklahoma. Oklahoma
City reported 4.33 inches of rain in six hours. Up to six inches of rain
caused flooding in north central Texas. (The National Weather Summary)
(Storm Data)

An F0 tornado struck a farm near Campbellsburg (Washington 
County Indiana). (NWS Louisville)

Lightning struck and injured a person in Lexington. (NWS Louisville)

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