Area Forecast Discussion
Issued by NWS Amarillo, TX

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS64 KAMA 200446 AAB
AFDAMA

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE AMARILLO TX
1046 PM CST FRI DEC 19 2014

.AVIATION...
IFR CONDITIONS WILL PREVAIL AT THE TAF SITES FOR MUCH OF THE
OVERNIGHT. LOW CIGS AND VISIBILITIES SHOULD IMPROVE AT ALL TAF SITES
BY MID TO LATE MORNING ON SATURDAY. SOUTH TO SOUTHWEST WINDS WILL
PREVAIL AT SPEEDS MAINLY UNDER 12 KNOTS.

&&

.PREV DISCUSSION... /ISSUED 554 PM CST FRI DEC 19 2014/

AVIATION...
FOR THE 00Z TAFS...MVFR CEILINGS REMAIN OVER THE EASTERN HALF OF THE
TEXAS AND OKLAHOMA PANHANDLES. CEILINGS ARE EXPECTED TO LOWER TO IFR
OVERNIGHT AND SPREAD WESTWARD...WITH LIFR/IFR CEILINGS AND FOG LIKELY
AGAIN EARLY SATURDAY MORNING. IFR CONDITIONS WILL SLOWLY LIFT TO MVFR
LATE MORNING AND SCATTER OUT AS SOUTHERLY WINDS TURN MORE
SOUTHWESTERLY AND INCREASE TO 8-15KTS BY AFTERNOON.

ELSENHEIMER

PREV DISCUSSION... /ISSUED 321 PM CST FRI DEC 19 2014/

DISCUSSION...

CLOUDS WILL PERSIST THROUGH TOMORROW MORNING WITH AREAS OF FOG ONCE
AGAIN DEVELOPING LATER THIS EVENING LASTING INTO THE MORNING HOURS.
LEE SURFACE TROUGH WILL STRENGTHEN/SHARPEN TOWARD MORNING ACROSS THE
FAR NORTHWEST PORTION OF THE FORECAST AREA AS A WEAK UPPER LEVEL
SHORTWAVE TROUGH MOVES TOWARD THE AREA. DEPENDING ON THE EXACT
POSITION OF THE LEE TROUGH SOME AREAS IN THE FAR NORTHWEST TEXAS
PANHANDLE AND FAR WESTERN OKLAHOMA PANHANDLE WILL HAVE SIGNIFICANTLY
REDUCED CHANCES OF FOG EITHER FORMING OR PERSISTING INTO THE LATE
NIGHT AND EARLY MORNING HOURS TOMORROW GIVEN DRIER WESTERLY SURFACE
FLOW BEHIND THE TROUGH. CONCERNED ABOUT POTENTIAL FOR LOW CLOUDS AND
FOG TO ONCE AGAIN LINGER LONGER THAN EXPECTED TOMORROW AND
IMPLICATIONS THAT MAY HAVE FOR HIGH TEMPERATURES. ADJUSTED
TEMPERATURES IN THE EAST DOWNWARD FOR TOMORROW TO ACCOUNT FOR THIS.
FOG MAY FORM ACROSS MAINLY THE EASTERN PORTION OF THE AREA TOMORROW
NIGHT. DRY CONDITIONS WILL PERSIST THROUGH THE WEEKEND.

THE LARGE SCALE PATTERN WILL BECOME SIGNIFICANTLY MORE AMPLIFIED
NEXT WEEK AS A STRONG MID-UPPER RIDGE BUILDS OFF THE CALIFORNIA
COAST AND A DEEP TROUGH EVOLVES OVER THE EASTERN CONUS. IN
BETWEEN...MEAN NORTHWESTERLY FLOW WILL BE PRESENT OVER THE PLAINS.
THE PRIMARY CHALLENGE IN THIS PATTERN IS VORTICITY MAXIMA ROTATING
AROUND DEVELOPING CLOSED LOW POTENTIALLY FORCING PERIODIC BRIEF
RELATIVELY INSIGNIFICANT PRECIPITATION EVENTS IN OUR REGION AS WELL
AS MODEST COLD SURGES. THE CHALLENGE WILL BE TIMING OF THESE
PERTURBATIONS. FROM AN ENSEMBLE MEAN PERSPECTIVE INDIVIDUAL WAVES ARE
DAMPENED OUT EXCEPT FOR THE ONE THAT MOVE THROUGH LATE MONDAY. THIS
SEEMS TO BE THE GREATEST CHANCE OF NOTEABLE SENSIBLE WEATHER CHANGES
THROUGH MID WEEK. MOISTURE AND ASCENT MAY BE SUFFICIENT FOR A SLIGHT
CHANCE OF PRECIPITATION ACROSS THE FAR NORTHWEST LATE MONDAY
SPREADING ACROSS THE AREA POTENTIALLY MONDAY NIGHT. COOLER
TEMPERATURES WILL ARRIVE BY LATE MONDAY WITH TIMING OF THE COLD FRONT
MAKING HIGH TEMPERATURE FORECAST A CHALLENGE. WITH POST FRONTAL
SURFACE PRESSURE GRADIENT AND SIGNIFICANT MOMENTUM ALOFT...AND AT
LEAST SOME POTENTIAL TO MIX INTO THAT...HAVE INCREASED WINDS FOR LATE
MONDAY THROUGH TUESDAY.

THEREAFTER A BRIEF PERIOD OF LOW AMPLITUDE RIDGING AND INCREASING
SOUTHWESTERLY DOWNSLOPE SURFACE FLOW WILL BRING WARMER TEMPERATURES
FOR CHRISTMAS DAY FOLLOWED BY A VIGOROUS TROUGH THAT WILL APPROACH
THE REGION BY FRIDAY. SURFACE RESPONSE SHOULD MAY BE FAIRLY DRAMATIC
WITH LEE TROUGH QUICKLY STRENGTHENING LATE ON CHRISTMAS DAY MORPHING
INTO A BROAD SURFACE LOW THURSDAY NIGHT INTO FRIDAY. TYPICAL
DIFFERENCES IN MEDIUM RANGE MODELS DO EXIST AT THAT RANGE WITH THE
12Z ECMWF BEING MUCH DEEPER AND STRONGER WITH SURFACE CYCLOGENESIS.
SO THERE SEEMS TO BE POTENTIAL FOR A GRADIENT WIND EVENT BY AROUND
FRIDAY. SUBSEQUENTLY A COLD FRONT WILL MOVE THROUGH BRING COLDER AIR
BY SATURDAY.

BOWERS

&&

.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.

&&

$$

15/05





USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.