Herculaneum, Missouri Weather Conditions

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Current Conditions

  • 86°
  • Clear
  • Wind: North -9999 mph
  • Humidity: 67%
  • Visibility: N/A
  • Dew Point: 74°
  • Pressure: 30.00 in. -
  • Heat Index: 94

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Next 12 Hours

10  am
1  pm
4  pm
7  pm
10  pm
Partly Cloudy
Partly Cloudy
Partly Cloudy
Partly Cloudy
Clear
Clear
Clear
Clear
Clear
Clear
84°
91°
95°
91°
86°
Forecast data from the National Digital Forecast Database.

5 Day Forecast

  • Thursday
  • Partly Cloudy
  • High: 97 °
  • Low: 75 °
  • Partly Cloudy
  • Friday
  • Partly Cloudy
  • High: 97 °
  • Low: 75 °
  • Partly Cloudy
  • Saturday
  • Clear
  • High: 97 °
  • Low: 73 °
  • Clear
  • Sunday
  • Clear
  • High: 99 °
  • Low: 73 °
  • Clear
  • Monday
  • Partly Cloudy
  • High: 95 °
  • Low: 75 °
  • Partly Cloudy

Forecast for Herculaneum, Missouri

Updated: 10:00 AM 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

    Clear. Low of 75F. Winds from the SSW at 5 to 10 mph.

  • Friday

    Clear in the morning, then partly cloudy. High of 97F with a heat index of 104F. Winds from the SW at 5 to 10 mph.

  • Friday Night

    Clear. Low of 75F. Winds from the SW at 5 to 10 mph.

  • Saturday

    Clear. High of 97F with a heat index of 104F. Winds less than 5 mph.

  • Saturday Night

    Partly cloudy in the evening, then clear. Low of 73F. Winds from the SSE at 5 to 10 mph.

  • Sunday

    Clear. High of 99F. Winds less than 5 mph.

  • Sunday Night

    Clear with a chance of a thunderstorm and rain after midnight. Low of 73F. Winds from the SE at 5 to 10 mph. Chance of rain 20%.

  • Monday

    Partly cloudy. High of 95F. Winds less than 5 mph.

  • Monday Night

    Partly cloudy. Low of 75F. Winds from the SE at 5 to 10 mph.

  • Tuesday

    Clear with a chance of a thunderstorm. High of 97F. Winds from the SE at 5 to 10 mph. Chance of rain 20%.

  • Tuesday Night

    Partly cloudy. Low of 73F. Winds from the SSE at 5 to 10 mph.

  • Wednesday

    Partly cloudy with a chance of a thunderstorm. High of 88F with a heat index of 97F. Winds from the South at 5 to 10 mph. Chance of rain 70% with rainfall amounts near 0.4 in. possible.

  • Wednesday Night

    Overcast with a chance of a thunderstorm. Low of 70F. Winds from the SSW at 5 to 10 mph shifting to the WNW after midnight. Chance of rain 40% with rainfall amounts near 0.2 in. possible.

  • Thursday

    Partly cloudy with a chance of rain. High of 81F. Winds from the NW at 5 to 10 mph. Chance of rain 20%.

  • Thursday Night

    Clear. Low of 54F. Winds less than 5 mph.

  • Friday

    Clear. High of 68F. Winds from the NNW at 5 to 10 mph.

  • Friday Night

    Clear. Low of 52F. Winds from the NNE at 5 to 10 mph.

  • Saturday

    Clear. High of 68F. Winds less than 5 mph.

  • Saturday Night

    Clear. Low of 52F. Winds less than 5 mph.

  • Sunday

    Clear. High of 72F. Winds less than 5 mph.

  • Sunday Night

    Clear. Low of 52F. Winds from the SE at 5 to 10 mph.

Severe Weather Alert Descriptions

 Heat Advisory  Statement as of 3:44 am CDT on August 21, 2014


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

* timing... dangerous levels of heat and humidity will continue
for the rest of the week and into the upcoming weekend.

* Heat index values... up to 105 due to temperatures in the 90s
and dewpoints in the lower 70s.

* 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: Sandy Creek Winery, Pevely, MO

Updated: 10:52 AM CDT

Temperature: 88.2 °F Dew Point: 77 °F Humidity: 69% Wind: NNW at 1.0 mph Pressure: 29.96 in Hourly Precipitation: 0.00 in Heat Index: 100 °F Graphs

Location: MesoWest MAEYS1 IL US UPR, Maeystown, IL

Updated: 10:05 AM CDT

Temperature: 80 °F Dew Point: - Humidity: - Wind: Calm Pressure: - Hourly Precipitation: 0.00 in Heat Index: 78 °F Graphs

Location: Imperial - Wellington Subdivision, Imperial, MO

Updated: 11:02 AM CDT

Temperature: 88.5 °F Dew Point: 78 °F Humidity: 70% Wind: West at 3.5 mph Pressure: 29.96 in Hourly Precipitation: 0.00 in Heat Index: 102 °F Graphs

Location: On The Bluffs, Waterloo, IL

Updated: 11:02 AM CDT

Temperature: 86.3 °F Dew Point: 77 °F Humidity: 73% Wind: Calm Pressure: 29.91 in Hourly Precipitation: 0.00 in Heat Index: 97 °F Graphs

Location: summerfield, Imperial, MO

Updated: 11:01 AM CDT

Temperature: 90.3 °F Dew Point: 77 °F Humidity: 65% Wind: Calm Pressure: 29.76 in Hourly Precipitation: 0.00 in Heat Index: 103 °F Graphs

Location: Imperial, MO

Updated: 11:02 AM CDT

Temperature: 79.0 °F Dew Point: 75 °F Humidity: 88% Wind: Calm Pressure: 29.93 in Hourly Precipitation: 0.00 in Heat Index: 83 °F Graphs

Location: Wynfield Terrace, St. Louis, MO

Updated: 11:02 AM CDT

Temperature: 85.8 °F Dew Point: 73 °F Humidity: 66% Wind: WSW at 2.0 mph Pressure: 30.00 in Hourly Precipitation: 0.00 in Heat Index: 93 °F Graphs

Location: Arnold, MO

Updated: 10:41 AM CDT

Temperature: 84.8 °F Dew Point: 78 °F Humidity: 79% Wind: SSW at 1.0 mph Pressure: 29.95 in Hourly Precipitation: 0.00 in Heat Index: 96 °F Graphs

Location: Arnold, Arnold, MO

Updated: 10:56 AM CDT

Temperature: 85.8 °F Dew Point: 76 °F Humidity: 72% Wind: Calm Pressure: 29.95 in Hourly Precipitation: 0.00 in Heat Index: 95 °F Graphs

Location: Oakville, Cliffwood Trail, Oakville, MO

Updated: 11:01 AM CDT

Temperature: 89.1 °F Dew Point: 77 °F Humidity: 67% Wind: Calm Pressure: 30.12 in Hourly Precipitation: 0.00 in Heat Index: 101 °F Graphs

Location: Christopher Winds, Oakville, MO

Updated: 10:50 AM CDT

Temperature: 85.1 °F Dew Point: 76 °F Humidity: 74% Wind: West at 1.0 mph Pressure: 29.95 in Hourly Precipitation: 0.00 in Heat Index: 95 °F Graphs

Location: Rock Creek Terrace, High Ridge, MO

Updated: 11:02 AM CDT

Temperature: 85.2 °F Dew Point: 76 °F Humidity: 75% Wind: WSW at 2.0 mph Pressure: 29.90 in Hourly Precipitation: 0.00 in Heat Index: 95 °F Graphs

Location: Hardy Acres / AA9UC, Waterloo, IL

Updated: 11:01 AM CDT

Temperature: 83.2 °F Dew Point: 60 °F Humidity: 46% Wind: South at 1.0 mph Pressure: 30.06 in Hourly Precipitation: 0.00 in Heat Index: 83 °F Graphs

Location: Oakville, Cardinal Creek Subd, Oakville, MO

Updated: 11:02 AM CDT

Temperature: 88.2 °F Dew Point: 78 °F Humidity: 71% Wind: SW at 3.0 mph Pressure: 29.96 in Hourly Precipitation: 0.00 in Heat Index: 101 °F Graphs

Location: Saint Louis County, Saint Louis County, MO

Updated: 11:00 AM CDT

Temperature: 85.9 °F Dew Point: 77 °F Humidity: 74% Wind: Calm Pressure: 29.99 in Hourly Precipitation: 0.00 in Heat Index: 97 °F Graphs

Location: Ste Genevieve county, Festus, MO

Updated: 11:01 AM CDT

Temperature: 86.0 °F Dew Point: - Humidity: - Wind: North at - Pressure: - Hourly Precipitation: 0.00 in Heat Index: - Graphs

Location: Oakville, Providence Pointe, Oakville, MO

Updated: 11:01 AM CDT

Temperature: 85.6 °F Dew Point: 75 °F Humidity: 70% Wind: South at 4.0 mph Pressure: 30.00 in Hourly Precipitation: 0.00 in Heat Index: 94 °F Graphs

Location: Olde Mill Estates, Byrnes Mill, MO

Updated: 11:01 AM CDT

Temperature: 86.9 °F Dew Point: 75 °F Humidity: 67% Wind: WSW at 6.0 mph Pressure: 30.10 in Hourly Precipitation: 0.00 in Heat Index: 96 °F Graphs

Location: Devall's Backyard, Waterloo, IL

Updated: 10:54 AM CDT

Temperature: 87.5 °F Dew Point: 73 °F Humidity: 63% Wind: North at 3.4 mph Pressure: 30.03 in Hourly Precipitation: - Heat Index: 95 °F Graphs

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

Updated: 10:48 AM CDT

Temperature: 86.7 °F Dew Point: 75 °F Humidity: 69% Wind: WSW at 14.0 mph Pressure: 29.94 in Hourly Precipitation: 0.00 in Heat Index: 96 °F Graphs

Location: Gedern Village, Columbia, IL

Updated: 11:02 AM CDT

Temperature: 86.9 °F Dew Point: 76 °F Humidity: 70% Wind: WSW at 2.0 mph Pressure: 30.00 in Hourly Precipitation: 0.00 in Heat Index: 97 °F Graphs

Location: APRSWXNET Mehlville MO US, Saint Louis, MO

Updated: 10:18 AM CDT

Temperature: 87 °F Dew Point: 78 °F Humidity: 75% Wind: Calm Pressure: 29.96 in Hourly Precipitation: 0.00 in Heat Index: 100 °F Graphs

Location: San Luis Trails, Fenton, MO

Updated: 11:02 AM CDT

Temperature: 86.1 °F Dew Point: 72 °F Humidity: 62% Wind: Calm Pressure: 29.91 in Hourly Precipitation: 0.00 in Heat Index: 92 °F Graphs

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

Updated: 11:00 AM CDT

Temperature: 88.0 °F Dew Point: - Humidity: 64% Wind: NW at 2.0 mph Pressure: 29.35 in Hourly Precipitation: 0.00 in Heat Index: 97 °F Graphs

Location: Hawkins/Smizer Mill, Fenton, MO

Updated: 11:02 AM CDT

Temperature: 88.1 °F Dew Point: 78 °F Humidity: 72% Wind: Calm Pressure: 29.94 in Hourly Precipitation: 0.00 in Heat Index: 102 °F Graphs

Location: St. Joseph Hill, Pacific, MO

Updated: 10:53 AM CDT

Temperature: 86.5 °F Dew Point: 76 °F Humidity: 71% Wind: WSW at 1.0 mph Pressure: 29.92 in Hourly Precipitation: 0.00 in Heat Index: 97 °F Graphs

Location: St. Louis, MO

Updated: 11:02 AM CDT

Temperature: 83.3 °F Dew Point: 77 °F Humidity: 81% Wind: Calm Pressure: 29.88 in Hourly Precipitation: 0.00 in Heat Index: 92 °F Graphs

Location: Gerry's Pool, Prairie Du Rocher, IL

Updated: 11:00 AM CDT

Temperature: 85.1 °F Dew Point: 74 °F Humidity: 70% Wind: East at 1.6 mph Pressure: 30.03 in Hourly Precipitation: 0.00 in Heat Index: 93 °F Graphs

Location: South County, Affton, MO

Updated: 11:02 AM CDT

Temperature: 86.1 °F Dew Point: 76 °F Humidity: 72% Wind: South at 4.0 mph Pressure: 29.92 in Hourly Precipitation: 0.00 in Heat Index: 96 °F Graphs

Location: K0GDI, Blackwell, MO

Updated: 11:02 AM CDT

Temperature: 87.5 °F Dew Point: 75 °F Humidity: 66% Wind: SSW at 1.0 mph Pressure: 29.85 in Hourly Precipitation: 0.00 in Heat Index: 97 °F Graphs

Location: Sunset Hills, St Louis, MO

Updated: 10:52 AM CDT

Temperature: 84.4 °F Dew Point: 76 °F Humidity: 76% Wind: Calm Pressure: 29.97 in Hourly Precipitation: - Heat Index: 94 °F Graphs

Location: Crestwood, Crestwood, MO

Updated: 11:01 AM CDT

Temperature: 87.4 °F Dew Point: 74 °F Humidity: 65% Wind: SSW at 3.7 mph Pressure: 29.70 in Hourly Precipitation: - Heat Index: 96 °F Graphs

Location: MesoWest KIDD1 IL US UPR,

Updated: 10:55 AM EDT

Temperature: 78 °F Dew Point: - Humidity: - Wind: Calm Pressure: - Hourly Precipitation: 0.00 in Heat Index: 76 °F Graphs

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

Updated: 11:00 AM CDT

Temperature: 86.4 °F Dew Point: 76 °F Humidity: 71% Wind: SSW at 1.0 mph Pressure: 29.95 in Hourly Precipitation: 0.00 in Heat Index: 97 °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 
501 am CDT Thu Aug 21 2014 


Short term: (through tonight) 
issued at 200 am CDT Thu Aug 21 2014 


Focus continues to be precip chances influencing temps thru the 
period. 


Mdls are in good agreement regarding synoptic features and mass 
fields. However, subtle differences in thermal profiles and 
mesoscale features will be important over the next few days. Main 
question is centered around ongoing convection over Nebraska and nrn 
Kansas. Believe the GFS handles this S/W the best tracking it thru 
cntl Iowa today along the sfc boundary. Any subsequent outflow 
boundaries will determine how far S convection will propagate this 
afternoon and tonight. Believe the area will remain dry this 
afternoon due to timing of the S/W as well as a lack of stronger 
forcing. A broad low level jet tonight shud be enuf forcing to support thunderstorms and rain 
that may impact nrn portions of the County Warning Area. The most likely timing 
will be late tonight at will at least in part depend upon how 
convection over Iowa region plays out today. 


As for temps, have trended twd the cooler guidance which has 
verified well even in places that did not see thunderstorms and rain over the past 
couple of days. Mdls are slightly cooler with 850mb temps over the 
region. For nrn counties, forecast soundings suggest those regions 
will not mix to 850mb anyway. Prelim forecast of 90 degrees at uin 
may be too warm due to convective debris. Further S, warmer temps 
will be offset by better mixing and therefore, cooler dewpoint 
temps. 


Overall, the resulting heat index values thru this afternoon are 
similar to what was forecast yesterday. Have therefore not made 
any changes to the going headlines. 


Long term: (friday through wednesday) 
issued at 309 am CDT Thu Aug 21 2014 


Focus continues to be temps thru the period with ongoing heat 
headlines. 


Overall, not many changes to the prev forecast. The Gem has come 
into better agreement with other mdl solns, but does still break 
down the upper ridge quicker. Questions regarding the need to 
expand the current advisory remain the same as they did yesterday. 
Mdls depict a weaker cap across much of the region, but especially 
across nrn portions of the County Warning Area. This area is also closer to the 
sfc boundary and may therefore experience more convective debris 
into the weekend, if not storms. Have therefore kept low pops 
going for this area and trended temps cooler. Elsewhere, continued 
a trend twd the cooler mav guidance as mentioned above. 


Mdl solns begin to diverge early next week with the European model (ecmwf) now 
reinforcing the upper ridge, keeping it in place thru the middle 
of the week. However, the GFS/Gem suggest a weaker upper ridge 
across the cntl U.S. Regardless, all mdl guidance suggests cooler 
mid level temps which may allow for afternoon/nocturnal convection 
across the region. Have kept pops on the low end until mdls come 
into better agreement and confidence builds. 


Due to questions mentioned, have not made any changes to the 
ending of the going headlines. However, headlines may need to be 
extended if the upper ridge holds into next week. 


&& 


Aviation: (for the 12z tafs through 12z Friday morning) 
issued at 456 am CDT Thu Aug 21 2014 


VFR conditions expected through this taf period. Some mid-level 
clouds will move through the kstl Metro taf sites this morning but 
otherwise only cirrus. Southwest winds will increase a bit today 
and may become gusty in the kcou area. 


Specifics for kstl: VFR conditions expected. Some mid-level clouds 
this morning but otherwise only scattered cirrus. Southwest winds 
will increase today but should remain at or below 10 knots. 


Browning 


&& 


Preliminary point temperatures/pops: 
Saint Louis 95 77 97 77 / 5 10 10 10 
Quincy 90 73 92 73 / 10 20 20 20 
Columbia 95 74 96 74 / 10 10 10 10 
Jefferson City 95 74 97 75 / 5 10 10 10 
Salem 93 74 92 74 / 20 10 10 10 
Farmington 93 73 95 73 / 20 10 10 5 


&& 


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-Greene Illinois-Jersey Illinois-Macoupin Illinois-Marion Illinois-Monroe 
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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