OrangeRoses's WunderBlog

Tu 112409

Posted by: OrangeRoses, 4:46 PM GMT on November 24, 2009

48 Hour Forecast Today - Thursday Thanksgiving Day

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SHREVEPORT LA
440 AM CST TUE NOV 24 2009.DISCUSSION...

COLD FRONT MAKING GOOD PROGRESS SEWD ACROSS SE OK/NCNTRL TX THIS MORNING...AND EXTENDS FROM A FSM...TO JUST E OF A TRL...TO CRS...TO E OF A ATT LINE AS OF 10Z. MEANWHILE...WIDELY SCT SHRA HAVE DEVELOPED AHEAD OF THE FRONT ACROSS SE OK/CNTRL-SW AR/EXTREME NE TX THIS MORNING ASSOCIATED WITH A THETA-E¹
RIDGE² ALONG THE NOSE OF A 30KT SWRLY LLJ³ IN PLACE. THE FRONT SHOULD REACH AN ELD TO IER TO JAS LINE BY 18Z BEFORE EXITING THE REGION BY EARLY EVENING. DEEP LYR MOISTURE WILL REMAIN QUITE LIMITED AHEAD OF THE FRONT...MAINLY CONFINED TO THE LOWEST SEVERAL THOUSAND
FEET...WITH ONLY LIMITED LARGE SCALE FORCING EXPECTED AS THE
PARENT TROUGHⁿ AXIS SLOWLY PROGRESSES E ACROSS THE CNTRL PLAINS/MS VALLEY TODAY. THUS...HAVE TAPERED POPS DOWN TO SLIGHT CHANCE...WITH A THIN SLIVER OF LOW CHANCE POPS ACROSS OUR FAR NRN SW AR COUNTIES WHERE SLIGHT BETTER FORCING IS EXPECTED AS WELL AS PORTIONS OF THE TOLEDO BEND RESERVOIR...WHERE LOW LEVEL MOISTURE WILL BE SLIGHTLY GREATER. ANY SHRA ACTIVITY SHOULD END BY MID/LATE AFTERNOON ACROSS NCNTRL LA...WITH THE FRONT REINFORCING COOLER AND DRIER AIR SWD IN ITS WAKEΘ. SOME OF THE PROTECTED AREAS
OF SE OK/SW AR MAY FLIRT WITH THE FREEZING MARK WEDNESDAY
MORNING...BUT THIN CIRRUS AND 10-15KT NW BNDRY LYR WINDS SHOULD KEEP THE AIR WELL ENOUGH MIXED TO KEEP TEMPS FROM FALLING TO SATURATION.

THE SFC Ω RIDGE BUILDING ACROSS WCNTRL TX WEDNESDAY WILL GRADUALLY SHIFT E OVER THE AREA BY AFTERNOON/NIGHT...WITH A 2ND LONGWAVE TROUGH EXPECTED TO RAPIDLY DIG SE THROUGH THE MS VALLEY EARLY THURSDAY. THIS WILL SEND ANOTHER REINFORCING SHOT OF COOLER AND DRIER AIR SWD INTO THE AREA EARLY THURSDAY AS WELL...

AMEN!

Glossary
1 Theta-e(or Equivalent Potential Temperature) The temperature a parcel of air would have if
a) it was lifted until it became saturated
b) all water vapor was condensed out and
c) it was returned adiabatically (i.e., without transfer of heat or mass) to a pressure of 1000 millibars.
Theta-e, which typically is expressed in degrees Kelvin, is directly related to the amount of heat present in an air parcel. Thus, it is useful in diagnosing atmospheric instability.

2 Ridge
1) An elongated area of relatively high atmospheric pressure; the opposite of trough.
or
2) In hydrologic terms, a line or wall of broken ice forced up by pressure. May be fresh or weathered

3 LLJ
Low Level Jet - A region of relatively strong winds in the lower part of the atmosphere. Specifically, it often refers to a southerly wind maximum in the boundary layer, common over the Plains states at night during the warm season (spring and summer). The term also may be used to describe a narrow zone of strong winds above the boundary layer, but in this sense the more proper term would be low-level jet stream.

n Trough
An elongated area of relatively low atmospheric pressure, usually not associated with a closed circulation, and thus used to distinguish from a closed low. The opposite of ridge.

Θ Wake
The region of turbulence immediately to the rear of a solid body caused by the flow of air over or around the body.

Ω SFC Surface

Don't get the flu. Don't spread the flu. Get Vaccinated. www.cdc.gov/flu

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Updated: 8:14 AM GMT on November 25, 2009

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W 111809

Posted by: OrangeRoses, 12:16 AM GMT on November 19, 2009

FREEZE

WARNING

TONIGHT

in effect from 9 PM this evening to 9 am CST Thursday...

The National Weather Service in Shreveport has issued a freeze warning...which is in effect from 9 PM this evening to 9 am CST Thursday.

Light winds...mostly clear skies...and a dry airmass will allow for temperatures to fall to slightly below freezing tonight. Temperatures could potentially remain below freezing from around midnight through daybreak Thursday morning.

Precautionary/preparedness actions...A freeze warning means sub-freezing temperatures are imminent or highly likely. These conditions will kill crops and other sensitive vegetation.

need leg warmers tomorrow

Brrrr or other 'tation' too! ► Φ

Updated: 12:18 AM GMT on November 19, 2009

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Sun 111509

Posted by: OrangeRoses, 6:48 PM GMT on November 15, 2009

I've been busy riding my bike a lot more lately in the encouraging cooler/pleasant Autumn weather.

►Today we have a weather maker!

[ Click for anime Doubleclick for still image ]

ETA first precipitation t-100 minutes and counting. The NWS used a graceful excuse for the predicted rain not to fall by mentioning dry values in the 850+ Millbar range which means absolutely nothing to most people, and why there is a keep it simple/stupid/brief one-liner forecast as well. I want it to rain and it will. How much remains to be determined; ► if you notice the general S Easterly movement of the N Easterly moving thunderstorm chain above, that will move over here and that will mean 0.5-1.5 inches of rain within an 8 hour period for this area!

The morning after... I had to wait 2 hours after my deadline posted above▲ for the first rain to fall, ƒƒƒinally, but indeed it did! In less than 1 hour - 10:10 - 10:50 PM - it rained heavily: 1.54in. | 39.11 mm.

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Updated: 11:01 PM GMT on November 16, 2009

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Tu 110309

Posted by: OrangeRoses, 9:40 AM GMT on November 03, 2009

The Land is starting to dry again. This allows for those (who love to rake leaves) to get leaves, not mud & leaves in their rakes. I don't rake the leaves- they somehow stay in the best place to decay to fertilize the ground. Much better, much easier, and intune than buying chemicals to crecen los milagros.