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McHenry County, IL Weather and Climate Synopsis

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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
359 PM CDT Thu Aug 16 2018

Mostly cloudy skies were seen across central and southeast 
Illinois this afternoon. Some isolated afternoon thunderstorms
formed over central Illinois. Temperatures around the area at 3 
PM, were in the lower and middle 80s.

As a low pressure system and associated frontal boundary continues
to move through the Midwest through the end of the week, low and 
mid level clouds will linger across the area. Showers and isolated
thunderstorms are possible across a large portion of the region 
this evening and linger through Friday. 

Overnight low temperatures, will range from the middle 50s across
northern Wisconsin, to the middle 70s across the Missouri bootheel
and the lower Ohio River Valley.

High temperatures on Friday, will reach the lower to middle 80s
across the Midwest.

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 1000 PM CDT THU AUG 16 2018

NORTHEAST ILLINOIS
  
CITY           SKY/WX    TMP DP  RH WIND       PRES   REMARKS
CHICAGO-OHARE  MOCLDY    77  68  73 E7        29.93S                  
CHICAGO-MIDWAY MOCLDY    77  70  79 E7        29.93S                  
AURORA         FAIR      74  71  91 CALM      29.93S                  
LANSING*       FAIR      73  67  81 E5        29.94F                  
JOLIET*        FAIR      78  69  75 E5        29.93S                  
WAUKEGAN       CLOUDY    74  70  87 CALM      29.95R                  
DUPAGE AIRPORT FAIR      76  68  76 SE5       29.94R                  
KANKAKEE*      FAIR      74  71  93 CALM      29.95R                  
WHEELING       CLOUDY    76  69  79 E3        29.95R                  
MORRIS*        FAIR      73  71  95 CALM      29.92R                  
ROMEOVILLE*    FAIR      74  68  81 E6        29.93S                  
NORTHERLY ISL    N/A     75  69  81 E7          N/A                   

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 1000pm CDT, Thursday August 16, 2018

Across Illinois...temperatures are near 67 degrees north, near 78 degrees central, and near 78 degrees south. Current sky conditions are thunderstorms north, fair central, and fair south. In the north, relative humidity is near 93%, and the dew point is near 65 degrees. In the central part of the state, relative humidity is near 93%, and the dew point is near 76 degrees. The heat index is near 81 degrees central. In the south, relative humidity is near 87%, and the dew point is near 74 degrees. The heat index is near 81 degrees south. The livestock heat stress category is no stress north, no stress central, and no stress south. There is patchy fog north. Winds are from the west at 17 mph with gusts at 26 mph north, where conditions are not favorable for spraying due to strong winds and thunderstorms. Winds are from the south at 7 mph central, where conditions are favorable for spraying. Winds are from the southwest at 3 mph south, where conditions are favorable for spraying. Based on current available observations, the highest temperature is 81 degrees at Pittsfield. The lowest temperature is 66 degrees at Freeport.


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

327 PM CDT Thu Aug 16 2018 /427 PM EDT Thu Aug 16 2018/

 DAY ONE  Tonight.

Weather hazards expected  

  Elevated Thunderstorm Risk...with an associated:
     Limited damaging wind risk...up to 60 mph.
  Limited Flooding Risk.

DISCUSSION  
Scattered thunderstorms are expected into the evening and possibly 
overnight. A few of the stronger storms may produce isolated 
damaging wind gusts, mainly in north central Illinois. In addition, 
the slow movement of any showers and storms will lead to the potential 
for isolated areas of one to two inches of rainfall in a short period
of time.

 DAYS TWO THROUGH SEVEN  Friday through Wednesday.

Friday  
  Limited Thunderstorm Risk.
Sunday  
  Limited Thunderstorm Risk.
Monday  
  Elevated Thunderstorm Risk.
Tuesday  
  Limited Lakeshore Flood Risk

 SPOTTER INFORMATION STATEMENT  

  Spotter activation will not be necessary through tonight.

GENERAL STORM MOTION OF THE DAY:

  Moving toward the northeast at 10 to 15 mph.

NWS Severe Weather Map , Convective Outlook


7-Day Forecast For MCHENRY County, IL
859 PM CDT Thu Aug 16 2018

REST OF TONIGHT
Mostly cloudy with a 50 percent chance of showers and thunderstorms. Patchy fog after midnight. Lows in the upper 60s. Northeast winds around 5 mph in the evening becoming north after midnight.

FRIDAY
Mostly cloudy with chance of showers and a slight chance of thunderstorms. Highs in the upper 70s. Northeast winds 5 to 10 mph. Chance of precipitation 50 percent.

FRIDAY NIGHT
Mostly clear. Lows in the lower 60s. North winds 5 to 10 mph.

SATURDAY
Mostly sunny. Highs in the lower 80s. Northeast winds 5 to 10 mph.

SATURDAY NIGHT
Clear. Lows in the lower 60s. Northeast winds 5 to 10 mph.

SUNDAY
Mostly sunny in the morning then becoming partly cloudy. Highs in the lower 80s.

SUNDAY NIGHT
Partly cloudy. Lows in the mid 60s.

MONDAY
Mostly cloudy with a 50 percent chance of showers and thunderstorms. Highs in the upper 70s.

MONDAY NIGHT
Mostly cloudy. Showers likely and a chance of thunderstorms in the evening, then a chance of showers after midnight. Lows in the lower 60s. Chance of precipitation 60 percent.

TUESDAY
Partly sunny. Highs in the mid 70s.

TUESDAY NIGHT THROUGH THURSDAY
Mostly clear. Lows in the mid 50s. 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
                             ILLINOIS                                                                     
                 ---------------------------------------------
                 6 TO 10 DAY  8 TO 14 DAY   30 DAY    90 DAY 
                   AUG 22-26    AUG 24-30    AUG       AUG-OCT                      
                 -----------  -----------  --------  ---------
   Temperature:      Below        Above      Above      Above                      
 Precipitation:      Below        Above     Normal      Below                      

....  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 August 16, 2018 the 228th Day of Year

---------------------------------------------------
SUN
Declination 13.420000
Distance 0.999717 AU
Rise 07:12 EDT Set 20:53 EDT
Transit Meridian 14:03 EDT
Civil Twilight Begins 06:45 EDT Ends 21:21 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

........................
AUGUST 16TH...HISTORIC WEATHER EVENTS
...1777...
The Battle of Bennington, delayed a day by rain, was fought. The rain
delayed British reinforcements, and allowed the Vermont Militia to arrive
in time, enabling the Americans to win a victory by defeating two enemy
forces, one at a time. (David Ludlum)
...1909...
A dry spell began in San Bernardino County of southern California that
lasted until the 6th of May in 1912, a stretch of 994 days! Another dry
spell, lasting 767 days, then began in October of 1912. (The Weather
Channel)
...1916...
Altapass NC was deluged with 22.22 inches of rain in 24 hours to establish
a state record. (The Weather Channel)
...1987...
Afternoon and evening thunderstorms developing along a cold front produced
severe weather from Oklahoma to Wisconsin and Lower Michigan. Thunderstorms
in central Illinois produced wind gusts to 80 mph at Springfield which
toppled two large beer tents at the state fair injuring 58 persons.
Thunderstorms also drenched Chicago IL with 2.90 inches of rain, making
August 1987 their wettest month of record. (The National Weather Summary)
(Storm Data)
...1988...
Thunderstorms developing along a slow moving cold front produced severe
weather from North Dakota to Lower Michigan during the day. Nine tornadoes
were sighted in North Dakota, and thunderstorms also produced hail three
inches in diameter at Lakota ND, and wind gusts to 83 mph at Marais MI.
Thirty-seven cities in the northeastern U.S. reported record high
temperatures for the date, including Rockford IL with a reading of 104
degrees. (The National Weather Summary) (Storm Data)
...1989...
Late afternoon and evening thunderstorms in the Central High Plains Region
produced golf ball size hail at La Junta CO, Intercanyon CO, and Custer SD.
Afternoon thunderstorms over South Texas drenched Brownsville with 2.60
inches of rain. Fair skies allowed viewing of the late evening full lunar
eclipse from the Great Lakes Region to the Northern and Central Plains
Region, and across much of the western third of the country. (The National
Weather Summary) (Storm Data)


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