Arnold, Missouri Weather Conditions

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Current Conditions

  • 86°
  • Clear
  • Wind: SSE 7 mph
  • Humidity: 77%
  • Visibility: 10.0 miles
  • Dew Point: 78°
  • Pressure: 29.89 in. 0
  • Heat Index: 98

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Next 12 Hours

10  pm
1  am
4  am
7  am
10  am
Overcast
Overcast
Clear
Clear
Clear
Clear
Clear
Clear
Clear
Clear
82°
81°
79°
75°
84°
Forecast data from the National Digital Forecast Database.

5 Day Forecast

  • Friday
  • Clear
  • High: 97 °
  • Low: 75 °
  • Clear
  • Saturday
  • Clear
  • High: 95 °
  • Low: 73 °
  • Clear
  • Sunday
  • Clear
  • High: 95 °
  • Low: 73 °
  • Clear
  • Monday
  • Clear
  • High: 95 °
  • Low: 73 °
  • Clear
  • Tuesday
  • Chance of a Thunderstorm
  • High: 93 °
  • Low: 73 °
  • Chance of T-Storms

Forecast for Arnold, Missouri

Updated: 10:00 PM CDT on August 21, 2014

Heat advisory in effect until 7 PM CDT Sunday...
  • Thursday

    Partly cloudy. High of 97F with a heat index of 104F. Winds from the SSW at 5 to 10 mph.

  • Thursday Night

    Overcast in the evening, then clear. Low of 73F. Winds from the SSW at 5 to 10 mph.

  • Friday

    Clear. High of 97F with a heat index of 106F. Winds from the SW at 5 to 10 mph.

  • Friday Night

    Clear. Low of 75F. Winds less than 5 mph.

  • Saturday

    Clear. High of 95F with a heat index of 102F. Winds less than 5 mph.

  • Saturday Night

    Clear. Low of 73F. Winds less than 5 mph.

  • Sunday

    Clear. High of 95F with a heat index of 100F. Winds less than 5 mph.

  • Sunday Night

    Clear. Low of 73F. Winds from the SE at 5 to 10 mph.

  • Monday

    Clear. High of 95F. Winds less than 5 mph.

  • Monday Night

    Partly cloudy in the evening, then clear with a chance of a thunderstorm and rain. Low of 73F. Winds from the SE at 5 to 10 mph. Chance of rain 20%.

  • Tuesday

    Partly cloudy with a chance of a thunderstorm and rain. High of 93F. Winds from the South at 5 to 10 mph. Chance of rain 40%.

  • Tuesday Night

    Partly cloudy with a chance of a thunderstorm. Fog overnight. Low of 73F. Winds from the SSE at 5 to 10 mph. Chance of rain 50% with rainfall amounts near 0.2 in. possible.

  • Wednesday

    Partly cloudy with a chance of a thunderstorm. High of 86F with a heat index of 97F. Winds from the South at 5 to 15 mph. Chance of rain 60% with rainfall amounts near 0.3 in. possible.

  • Wednesday Night

    Partly cloudy with a chance of a thunderstorm. Fog overnight. Low of 70F. Winds from the SSW at 5 to 10 mph. Chance of rain 40% with rainfall amounts near 0.3 in. possible.

  • Thursday

    Partly cloudy with a chance of a thunderstorm. High of 82F. Winds from the WNW at 5 to 10 mph. Chance of rain 50%.

  • Thursday Night

    Clear. Low of 57F. Winds less than 5 mph.

  • Friday

    Clear. High of 81F. Winds less than 5 mph.

  • Friday Night

    Clear. Low of 63F. Winds less than 5 mph.

  • Saturday

    Clear. High of 81F. Winds less than 5 mph.

  • Saturday Night

    Clear. Fog overnight. Low of 64F. Winds less than 5 mph.

  • Sunday

    Clear. High of 82F. Winds less than 5 mph.

  • Sunday Night

    Clear. Low of 66F. Winds less than 5 mph.

  • Monday

    Clear. High of 82F. Winds less than 5 mph.

  • Monday Night

    Clear. Fog overnight. Low of 66F. Winds less than 5 mph.

Severe Weather Alert Descriptions

 Heat Advisory  Statement as of 3:49 PM CDT on August 21, 2014


... Heat advisory remains in effect until 7 PM CDT Sunday...

* timing... dangerous levels of heat and humidity will continue
through the weekend.

* Heat index values... up to 106.

* Impacts... the combination of hot temperatures and high
humidity will likely lead to an increased risk of heat-
related stress and illness. The very Young... the elderly...
those without air conditioning... and those participating in
strenuous outdoor activities will be the most susceptible.
Also... car interiors can reach lethal temperatures in a matter
of minutes. Beat the heat... check the backseat! Never leave
children or pets unattended in a vehicle... not even for a
minute.

Precautionary/preparedness actions...

Take extra precautions if you work or spend time outside. When
possible... reschedule strenuous activities to the early morning
or evening. Know the signs and symptoms of heat exhaustion and
heat stroke. Wear light weight and loose fitting clothing when
possible and drink plenty of water.

To reduce risk during outdoor work... the occupational safety and
health administration recommends scheduling frequent rest breaks
in shaded or air conditioned environments. Anyone overcome by
heat should be moved to a cool and shaded location. Heat stroke
is an emergency. Call 9-1-1 immediately.





Personal Weather Stations

Personal Weather Stations [Add your weather station!]

Location: Arnold, MO

Updated: 8:56 PM CDT

Temperature: 83.4 °F Dew Point: 79 °F Humidity: 87% Wind: Calm Pressure: 29.86 in Hourly Precipitation: 0.00 in Heat Index: 95 °F Graphs

Location: Arnold, Arnold, MO

Updated: 8:57 PM CDT

Temperature: 85.3 °F Dew Point: 77 °F Humidity: 77% Wind: SSE at 2.0 mph Pressure: 29.86 in Hourly Precipitation: 0.00 in Heat Index: 96 °F Graphs

Location: summerfield, Imperial, MO

Updated: 8:57 PM CDT

Temperature: 79.9 °F Dew Point: 79 °F Humidity: 96% Wind: Calm Pressure: 29.67 in Hourly Precipitation: 0.00 in Heat Index: 86 °F Graphs

Location: Wynfield Terrace, St. Louis, MO

Updated: 8:57 PM CDT

Temperature: 83.1 °F Dew Point: 72 °F Humidity: 70% Wind: South at 2.2 mph Pressure: 29.94 in Hourly Precipitation: 0.00 in Heat Index: 89 °F Graphs

Location: Saint Louis County, Saint Louis County, MO

Updated: 8:55 PM CDT

Temperature: 83.6 °F Dew Point: 78 °F Humidity: 82% Wind: Calm Pressure: 29.90 in Hourly Precipitation: 0.00 in Heat Index: 94 °F Graphs

Location: Imperial, MO

Updated: 8:57 PM CDT

Temperature: 80.4 °F Dew Point: 75 °F Humidity: 84% Wind: Calm Pressure: 29.85 in Hourly Precipitation: 0.00 in Heat Index: 86 °F Graphs

Location: Oakville, Providence Pointe, Oakville, MO

Updated: 8:57 PM CDT

Temperature: 85.8 °F Dew Point: 77 °F Humidity: 75% Wind: Calm Pressure: 29.92 in Hourly Precipitation: 0.00 in Heat Index: 97 °F Graphs

Location: Imperial - Wellington Subdivision, Imperial, MO

Updated: 8:57 PM CDT

Temperature: 85.0 °F Dew Point: 78 °F Humidity: 80% Wind: Calm Pressure: 29.87 in Hourly Precipitation: 0.00 in Heat Index: 97 °F Graphs

Location: Oakville, Cliffwood Trail, Oakville, MO

Updated: 8:57 PM CDT

Temperature: 83.8 °F Dew Point: 77 °F Humidity: 79% Wind: Calm Pressure: 30.00 in Hourly Precipitation: 0.00 in Heat Index: 93 °F Graphs

Location: Oakville, Cardinal Creek Subd, Oakville, MO

Updated: 8:57 PM CDT

Temperature: 85.3 °F Dew Point: 78 °F Humidity: 80% Wind: SSE at 1.0 mph Pressure: 29.88 in Hourly Precipitation: 0.00 in Heat Index: 98 °F Graphs

Location: Christopher Winds, Oakville, MO

Updated: 8:36 PM CDT

Temperature: 84.7 °F Dew Point: 78 °F Humidity: 80% Wind: SE at 1.0 mph Pressure: 29.86 in Hourly Precipitation: 0.00 in Heat Index: 96 °F Graphs

Location: Rock Creek Terrace, High Ridge, MO

Updated: 8:57 PM CDT

Temperature: 81.5 °F Dew Point: 76 °F Humidity: 84% Wind: Calm Pressure: 29.81 in Hourly Precipitation: 0.00 in Heat Index: 89 °F Graphs

Location: South St. Louis County, St. Louis, MO

Updated: 8:56 PM CDT

Temperature: 88.7 °F Dew Point: - Humidity: 65% Wind: SE at 3.0 mph Pressure: 29.27 in Hourly Precipitation: 0.00 in Heat Index: 99 °F Graphs

Location: San Luis Trails, Fenton, MO

Updated: 8:57 PM CDT

Temperature: 84.9 °F Dew Point: 75 °F Humidity: 72% Wind: Calm Pressure: 29.82 in Hourly Precipitation: 0.00 in Heat Index: 93 °F Graphs

Location: High Ridge Fire District House #1, High Ridge, MO

Updated: 8:49 PM CDT

Temperature: 88.1 °F Dew Point: 76 °F Humidity: 68% Wind: SE at 8.0 mph Pressure: 29.85 in Hourly Precipitation: 0.01 in Heat Index: 99 °F Graphs

Location: St. Louis, MO

Updated: 8:57 PM CDT

Temperature: 85.6 °F Dew Point: 78 °F Humidity: 77% Wind: ENE at 1.0 mph Pressure: 29.78 in Hourly Precipitation: 0.00 in Heat Index: 97 °F Graphs

Location: Hawkins/Smizer Mill, Fenton, MO

Updated: 8:57 PM CDT

Temperature: 85.7 °F Dew Point: 78 °F Humidity: 77% Wind: Calm Pressure: 29.85 in Hourly Precipitation: 0.00 in Heat Index: 97 °F Graphs

Location: Sunset Hills, St Louis, MO

Updated: 8:48 PM CDT

Temperature: 87.5 °F Dew Point: 78 °F Humidity: 73% Wind: Calm Pressure: 29.87 in Hourly Precipitation: - Heat Index: 100 °F Graphs

Location: Crestwood, Crestwood, MO

Updated: 8:52 PM CDT

Temperature: 84.4 °F Dew Point: 75 °F Humidity: 73% Wind: Calm Pressure: 29.62 in Hourly Precipitation: - Heat Index: 92 °F Graphs

Location: South County, Affton, MO

Updated: 8:57 PM CDT

Temperature: 86.3 °F Dew Point: 79 °F Humidity: 80% Wind: Calm Pressure: 29.84 in Hourly Precipitation: 0.00 in Heat Index: 101 °F Graphs

Location: Olde Mill Estates, Byrnes Mill, MO

Updated: 8:57 PM CDT

Temperature: 85.3 °F Dew Point: 77 °F Humidity: 77% Wind: SE at 3.8 mph Pressure: 30.00 in Hourly Precipitation: 0.00 in Heat Index: 96 °F Graphs

Location: Big Bend and I-270, Kirkwood, MO

Updated: 8:55 PM CDT

Temperature: 87.1 °F Dew Point: 76 °F Humidity: 71% Wind: Calm Pressure: 29.85 in Hourly Precipitation: 0.00 in Heat Index: 98 °F Graphs

Location: Gedern Village, Columbia, IL

Updated: 8:57 PM CDT

Temperature: 84.7 °F Dew Point: 77 °F Humidity: 77% Wind: Calm Pressure: 29.91 in Hourly Precipitation: 0.00 in Heat Index: 95 °F Graphs

Location: Crest Ave. Kirkwood MO, St. Louis, MO

Updated: 7:41 PM CDT

Temperature: 89.4 °F Dew Point: 76 °F Humidity: 66% Wind: Calm Pressure: 29.86 in Hourly Precipitation: - Heat Index: 102 °F Graphs

Location: East Madison, Kirkwood, MO, Kirkwood, MO

Updated: 8:57 PM CDT

Temperature: 85.8 °F Dew Point: 77 °F Humidity: 74% Wind: Calm Pressure: 29.91 in Hourly Precipitation: 0.00 in Heat Index: 96 °F Graphs

Location: On The Bluffs, Waterloo, IL

Updated: 8:57 PM CDT

Temperature: 80.5 °F Dew Point: 76 °F Humidity: 87% Wind: Calm Pressure: 29.81 in Hourly Precipitation: 0.00 in Heat Index: 87 °F Graphs

Location: Sandy Creek Winery, Pevely, MO

Updated: 8:55 PM CDT

Temperature: 79.5 °F Dew Point: 77 °F Humidity: 93% Wind: Calm Pressure: 29.87 in Hourly Precipitation: 0.00 in Heat Index: 85 °F Graphs

Location: Essex and Geyer, St. Louis, MO

Updated: 8:50 PM CDT

Temperature: 85.6 °F Dew Point: 76 °F Humidity: 72% Wind: Calm Pressure: 29.73 in Hourly Precipitation: - Heat Index: 95 °F Graphs

Location: Webster Groves, Webster Groves, MO

Updated: 8:55 PM CDT

Temperature: 86.4 °F Dew Point: 76 °F Humidity: 70% Wind: ESE at 4.0 mph Pressure: 29.96 in Hourly Precipitation: 0.00 in Heat Index: 96 °F Graphs

Location: Manchester, MO, Manchester, MO

Updated: 8:51 PM CDT

Temperature: 83.5 °F Dew Point: 77 °F Humidity: 80% Wind: Calm Pressure: 29.91 in Hourly Precipitation: 0.00 in Heat Index: 93 °F Graphs

MSN Maps of:

Temp: Dew Point: Humidity Wind Pressure Hr Precip -

NWS Forecaster Discussion




Area forecast discussion...updated aviation 
National Weather Service St Louis MO 
548 PM CDT Thu Aug 21 2014 


Short term: (through late tonight) 
issued at 307 PM CDT Thu Aug 21 2014 


Isolated thunderstorms are possible late this afternoon and early 
tonight over the Eastern Ozarks. 


Kanofsky 


Long term: (friday through next thursday) 
issued at 307 PM CDT Thu Aug 21 2014 


Overall thinking remains similar to previous forecasts. An upper 
level ridge is expected to remain in place through early next 
week, bringing dangerous levels of heat and humidity to the 
region. 850 mb temperatures of 20-24 deg c and h9 temperatures of 
24-28 deg c support daytime highs in the mid to upper 90s through 
early next week. Dew points are forecast to be in the 60s and 70s. 
Heat index values will likely exceed 100 deg f each afternoon 
across most of the lsx cwa, and some locations will likely reach 
heat index values of 105-107 f. There remains a question about 
whether dew points will mix out over the Ozarks on one or more 
days during this stretch of hot weather, resulting in lower heat 
index values. Since the heat advisory was issued primarily for 
duration (4 days of heat index values exceeding 100 deg f), we 
will wait to see how afternoon dew points respond and will hold 
off on expanding the heat advisory to the southwest. The heat 
advisory will be expanded eastward to include two more Illinois 
counties after collaboration with neighboring offices. No changes 
were made to the excessive heat warning. 


Latest models continue to depict significant differences regarding 
how/if/when the upper ridge breaks down next week. These 
differences Stem from how the models handle the interaction 
between a shortwave moving down the Pacific northwest coast and a 
closed low over Mt/WY. European model (ecmwf)/Gem both have less phasing and nearly 
develop a cutoff low over Nevada/Utah while the GFS has greater phasing 
between these features and is much more progressive with the 
overall pattern. Generally followed the recommended CR 
initialization for the extended forecast periods pending improved 
model agreement. Although there may be some isolated 
thunderstorms (especially over the ozarks), there appears to be 
very little chance for widespread rainfall until the middle of 
next week. 


Kanofsky 


&& 


Aviation: (for the 00z tafs through 00z Friday evening) 
issued at 541 PM CDT Thu Aug 21 2014 


VFR conditions are expected for the valid taf period with 
generally light winds backing to the south-southwest tonight before veering 
more southwesterly by Friday morning. Cannot rule out the 
possibility of some storms tonight...of most concern would be 
KUIN. For now will leave tafs dry however as believe greater 
coverage of activity will most likely remain north of County Warning Area. 




Specifics for kstl: 


VFR conditions are expected for the valid taf period with 
generally light winds backing to the south-southwest tonight before veering 
more southwesterly by Friday morning. Cannot rule out the 
possibility of some storms tonight...but for now will leave taf dry 
as believe most if not all activity will remain well north of terminal. 


Gosselin 


&& 


Lsx watches/warnings/advisories: 
MO...heat advisory until 7 PM CDT Sunday for Audrain MO-Boone MO- 
Callaway MO-Cole MO-Franklin MO-Gasconade MO-Jefferson MO- 
Lincoln MO-Madison MO-Moniteau MO-Montgomery MO-Osage MO- 
St. Charles MO-St. Francois MO-Ste. Genevieve MO-Warren MO. 


Excessive heat warning until 7 PM CDT Sunday for St. Louis city 
MO-St. Louis MO. 


Illinois...heat advisory until 7 PM CDT Sunday for Bond Illinois-Calhoun Illinois- 
Clinton Illinois-Fayette Illinois-Greene Illinois-Jersey Illinois-Macoupin Illinois- 
Marion Illinois-Monroe Illinois-Montgomery Illinois-Randolph Illinois-Washington Illinois. 


Excessive heat warning until 7 PM CDT Sunday for Madison IL-St. 
Clair Illinois. 


&& 


$$ 


Weather forecast office lsx 












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