Daytime highs for Monday thru Thursday will wobble around in the mid 100s every day, with little variation in the weather pattern we have encountered the last few days. Partly cloudy skies are possible Monday and slightly breezy conditions on Tuesday, otherwise it will be clear skies, calm air and hot. Humidity will drop slightly after Monday which will put us just under heat advisory criteria.

A cool front is forecast to move through the area on Friday, which will encounter rich moisture that is also forecast to be in the area. These two combined will create conditions favorable for thunderstorms anytime from Thursday night through Friday. Storms may be possible this weekend as well but confidence in this is low and only a 10% chance is in the forecasts. Daytime highs on Friday are only 94 degrees due to the increased cloud cover and rain cooled air. No severe weather is anticipated at this time.

On a side note, NOAA has observed El Nino conditions in the Pacific Ocean, which is likely to persist into 2010. This means the Pacific Ocean is about 1 degree celcius above normal, altering weather patterns globally. I did a little research on this and an El Nino winter in North Texas means wetter, stormier and warmer than normal. This compares with the past winter in which the Pacific Ocean was exactly neutral. Neutral conditions are a tad ambiguious for this area with weather extremes of all types occuring. However, the most intense wintertime snow falls in north Texas occur during neutral years, this past winter being an exception. When I looked at long range climbate forecasts for this area the forecasts do agree with El Nino conditions, bringing warmer than normal and wetter than normal conditions to the area for winter.

Currently a heat advisory has been issued for Dallas and Tarrant counties as heat index values are expected to exceed 105 degrees.

A cold front is set to move through the area overnight however, possibly bringing heavy rains and thunderstorms beginning in the very early morning hours Sunday, possibly before sunrise. Rain chances will move through the area north to south so I don’t believe Frisco will get rained out until everyone is already back home, but if this changes than I will do my best to send out an update. Sunday, Monday and Tuesday high temps only have us reaching the low 90s which appears due to the increased cloudiness, rainfall and northerly winds after the cold front passage.

…Fourth of July heat will be felt across much of North Texas today…

Overnight lows have remained in the lower 80s for all urban locations within North Texas. Mostly sunny skies are expected tobring afternoon temperatures at or above the century mark todaywhile afternoon relative humidity values remain at or above 30percent. The combination of heat and humidity will bring heat indices up to 105 degrees during the peak heating hourstoday…especially across the metroplex and around Waco. With manypeople outdoors enjoying Independence day festivities…thepotential for heat stress to affect many people is greater than on most Summer days. A cold front is expected to move slowly souththrough North Texas overnight bringing some relief from the heatas temperatures are expected to fall into the middle 70s.

If outdoors this Independence day…remember to drink plenty of non alcoholic beverages to remain hydrated to avoid the effects ofheat stress. When possible take a break from the heat and get outof the sun. The effects of heat stress are felt much faster bychildren and by the elderly.

Friday will be just as hot as Thursday, with high temps just over 100 degrees. Dew points will be about the same as well, sitting around 60 to 65 degrees. This creates heat index values around 105F, just shy of heat advisory criteria. Air pollution watch level Orange is issued for Friday, just like every other day this week. Skies will be clear and winds from the south at 5-10mph. Nothing too special for Friday, other than very bright clear skies and hot.

Saturday will be marginally cooler than Friday, with high temps around 100 and heat index values around 105. Mostly clear skies, air pollution watch level orange, and southwest winds 10 to 15mph. If your spending any amount of time outside Saturday, remember the sunblock and water. No rain is forecast so aside from the heat, Saturday will be an excellent outdoor day.

A cold front is expected to push through the area either Sunday or Monday. Computer models are having a hard time pinpointing the time when it will actually move through, but it will happen. At this time, rain chances can occur around Frisco anytime from maybe Sunday midday through Monday night. There is not alot of confidence in the timing of this however, so this is subject to change. Rain chances are only at 20% at this time and no severe weather is anticipated. Temperatures on Monday will be cooler due to this front, with high temps only expected to reach 90 degrees. Temps bounce back quickly on Tuesday and beyond though as temps are forecast to reach or exceed 95 degrees.

Have a happy 4th everyone!

Essentially not only will it be extremely hot outside, the air is also very hazardous to breathe. So this means if you don’t collapse from heat stroke within 15 minutes, you may collapse from some severe respiratory aliment due to the horrible quality air, fun huh!?

Yesterday, June 23, was the first day of the season to see 100 degree temperatures at DFW Airport. Statement from the NWS is below.

…First 100-degree day of the season at dfw Airport…

At 243 PM CDT…the temperature at dfw Airport reached 100 degrees.
This is the first triple-digit high temperature of the season.

For Dallas/Fort Worth…the average date of the first 100-degree day
is July 1. This date varies considerably as recent years show…

2008   June 15
2007   August 11
2006   April 17

The average number of triple-digit highs for the season is 16…but
this too can vary greatly from year to year…

2008   30
2007    5
2006   43   (7th most on record)
2005   18
2004    1
2003   19
2002    1

The most 100-degree days in any year is 69 in 1980. There have been
two years without any triple-digit readings…1973 and 1906. (The
highest temperature was 99 degrees in both years.)

———————————-

…Heat advisory in effect from 2 PM this afternoon to 8 PM CDT
Thursday…

The National Weather Service in Fort Worth has issued a heat

advisory…which is in effect from 2 PM this afternoon to 8 PM
CDT Thursday.

Morning low temperatures of 78 degrees combined with afternoon
heat indices above 105 degrees have prompted a heat advisory
for the urban areas of the dfw metroplex. The advisory will last

through sunset Thursday.

Precautionary/preparedness actions…

A heat advisory means that afternoon heat index values are
expected to meet or exceed 105 degrees while overnight low
temperatures will not fall below the upper 70s. Persons involved

in vigorous outdoor activities are urged to take frequent breaks
and drink plenty of water. Wear loose fitting and light-colored
clothing. Be sure to check on persons with health problems and
the elderly…as they are the most susceptible to heat exhaustion

and heat stroke. Never leave Young children or pets in an
enclosed vehicle…even for a short time…as temperatures can
quickly rise to life threatening levels.

…AIR POLLUTION WATCH LEVEL RED…

AIR POLLUTION WATCH – LEVEL RED – FOR DALLAS-FORT WORTH.

THE TEXAS COMMISSION ON ENVIRONMENTAL QUALITY (TCEQ) HAS ISSUED A
LEVEL RED AIR POLLUTION WATCH FOR THE DALLAS-FORT WORTH AREA FOR
WEDNESDAY, JUNE 24, 2009.

ATMOSPHERIC CONDITIONS ARE EXPECTED TO BE FAVORABLE FOR PRODUCING
HIGH LEVELS OF OZONE AIR POLLUTION IN THE DALLAS-FORT WORTH AREA
ON WEDNESDAY. OZONE LEVELS COULD REACH THE LEVEL RED “UNHEALTHY”
CATEGORY.

ELEVATED CONCENTRATIONS OF OZONE CAN ACT AS A LUNG IRRITANT.
INDIVIDUALS WITH CHRONIC LUNG DISEASE, SUCH AS ASTHMA AND
EMPHYSEMA, AS WELL AS THE ELDERLY AND YOUNG CHILDREN, ARE
PARTICULARLY SENSITIVE TO OZONE AND SHOULD ATTEMPT TO AVOID
EXPOSURE.  TO AVOID EXPOSURE, MINIMIZE EXERTION OUTDOORS DURING
THE MID-DAY TO EARLY EVENING HOURS OR STAY INDOORS IN AN AIR-
CONDITIONED ROOM DURING THIS TIME.

FOR MORE INFORMATION ON OZONE, VISIT THE TCEQ OZONE DATA PAGE:
(USE LOWER CASE LETTERS)
WWW.TCEQ.STATE.TX.US/NAV/DATA/OZONE_DATA.HTML

Currently storm development is occurring along a residual boundary stretching from Citrus county through Lakeland, and down towards Sebring. The overall movement of these storms is to the SSE, but these storms do have the potential to propogate away if a strong outflow boundary develops from these.

Additionally another heat advisory has been issued since afternoon temps are sitting in the mid to upper 90s inland, near 90 at the coast. This is creating heat index values of 105-110F, extremely hot conditions for Florida.

URGENT – IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 499
NWS STORM PREDICTION CENTER NORMAN OK
235 PM EDT TUE JUN 23 2009

THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

FLORIDA
COASTAL WATERS

EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 235 PM UNTIL
900 PM EDT.

HAIL TO 2 INCHES IN DIAMETER…THUNDERSTORM WIND GUSTS TO 70
MPH…AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 60
STATUTE MILES EAST AND WEST OF A LINE FROM 20 MILES NORTHEAST OF
OCALA FLORIDA TO 55 MILES SOUTH OF MIAMI FLORIDA.  FOR A COMPLETE
DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE
(WOUS64 KWNS WOU9).

REMEMBER…A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.

OTHER WATCH INFORMATION…THIS SEVERE THUNDERSTORM WATCH REPLACES
SEVERE THUNDERSTORM WATCH NUMBER 495. WATCH NUMBER 495 WILL NOT
BE IN EFFECT AFTER 235 PM EDT. CONTINUE…WW 496…WW 497…WW
498…

DISCUSSION…SEASONABLY STRONG NLY FLOW ALOFT WILL CONTINUE ACROSS
FL THIS AFTERNOON/EVENING AS DEEP MID LEVEL TROUGH DIGS OFF THE NERN
FL COAST.  AIR MASS REMAINS VERY UNSTABLE…DESPITE EARLIER LINEAR
MCS…WITH SUFFICIENT SHEAR FOR ORGANIZATION INTO LINES/CLUSTERS AND
PERHAPS A BRIEF SUPERCELL OR TWO.  DAMAGING WINDS AND ISOLATED LARGE
HAIL WILL REMAIN PRIMARY THREATS…ALTHOUGH A BRIEF
WATERSPOUT/TORNADO COULD ACCOMPANY STORMS ALONG RESIDUAL SURFACE
BOUNDARIES.

AVIATION…A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM
MOTION VECTOR 33030.