Area Forecast Discussion
Issued by NWS Columbia, SC

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
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
FXUS62 KCAE 011210
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
810 AM EDT SUN MAY 1 2016

.SYNOPSIS...
A MOIST SOUTHERLY FLOW WILL CONTINUE INTO THE FORECAST AREA
THROUGH MONDAY AHEAD OF A SLOW MOVING COLD FRONT. THE FRONT WILL
BE NEAR THE REGION TUESDAY AND WEDNESDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
QUICK UPDATE THIS MORNING TO ADJUST POPS HIGHER ACROSS THE
NORTHERN AND CENTRAL MIDLANDS TO ACCOUNT FOR CONVECTION
ASSOCIATED WITH A PASSING SHORTWAVE. THERE IS SOME THREAT FOR
LOCALIZED FLOODING ACROSS NORTHERN MIDLANDS...ESPECIALLY NORTHERN
LANCASTER COUNTY AS 1-3 INCHES OF ADDITIONAL RAINFALL POSSIBLE
THIS MORNING AFTER NEARLY 3-4 INCHES FELL IN STORMS LAST NIGHT.

PREVIOUS DISCUSSION
TODAY...A MOIST LOW-LEVEL SOUTHERLY FLOW WILL CONTINUE. SHOWERS
AND THUNDERSTORMS SUPPORTED BY A MID-LEVEL SHORTWAVE TROUGH SHOULD
AFFECT MUCH OF THE FORECAST AREA THIS MORNING. WATER VAPOR IMAGERY
TRENDS SUPPORT MOISTURE MORE SHALLOW BEHIND THE UPPER FEATURE LATE
THIS MORNING AND THIS AFTERNOON. HAVE FORECASTED THE HIGHEST POPS
THIS MORNING. EARLY CONVECTION SHOULD LIMIT INSTABILITY BUT THE
NAM INDICATED SURFACE-BASED LI/S -5 TO -7. THE MODERATE
INSTABILITY AND DRY MID-LEVEL AIR AIDING DOWNDRAFTS SUPPORTS SOME
POSSIBILITY OF DAMAGING WIND WITH THE THUNDERSTORMS. WET BULB ZERO
HEIGHTS ALSO FAVOR HAIL. FOLLOWED THE GUIDANCE CONSENSUS FOR THE
TEMPERATURE FORECAST.

TONIGHT...THE MOIST LOW-LEVEL FLOW WILL CONTINUE. ANOTHER IN A
SERIES OF MID-LEVEL SHORTWAVE TROUGHS SHOULD AFFECT THE AREA BUT
THE MODELS INDICATE WEAK LIFT. THE GUIDANCE CONSENSUS SUPPORTED
CHANCE POPS. CLOUDINESS AND MIXING SHOULD HELP HOLD UP
TEMPERATURES. THE GUIDANCE WAS CLOSE.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY/...
THE MOIST LOW-LEVEL SOUTHERLY FLOW AHEAD OF THE SLOW MOVING COLD
FRONT WILL CONTINUE THROUGH MONDAY NIGHT. THERE WAS MODEL
INCONSISTENCY WITH UPPER LIFT MONDAY...BUT MORE AGREEMENT WITH A
MID-LEVEL SHORTWAVE TROUGH MOVING INTO THE AREA MONDAY NIGHT.
FORECASTED CHANCE POPS MONDAY...AND LIKELY MONDAY NIGHT...
ESPECIALLY DURING THE EVENING CLOSER TO MAXIMUM HEATING. THE
TEMPERATURE GUIDANCE WAS CONSISTENT.

THE MODELS DISPLAYED THE COLD FRONT IN THE FORECAST AREA TUESDAY.
THERE MAY BE DIMINISHED MOISTURE BEHIND A MID-LEVEL SHORTWAVE
TROUGH. THE ECMWF DEPICTED THE MOST MOISTURE. WE FORECASTED
CHANCE POPS WHICH WAS SUPPORTED BY THE NAM AND GFS MOS. FOLLOWED
THE GUIDANCE CONSENSUS FOR THE TEMPERATURE FORECAST.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
THERE HAS BEEN LITTLE CONSISTENCY WITH THE PLACEMENT OF LOW
PRESSURE FORECAST TO DEVELOP ALONG THE FRONT NEAR THE FORECAST
AREA TUESDAY NIGHT OR WEDNESDAY. DRYING MAY DOMINATE THURSDAY
THROUGH SATURDAY WITH NORTHWEST AND DOWNSLOPE FLOW ASSOCIATED
WITH THE LOW NORTH OF THE REGION. HOWEVER...AN H5 CUT-OFF LOW AND
ASSOCIATED INSTABILITY MAY BE CLOSE ENOUGH TO THE AREA FOR A
CONTINUED CHANCE OF SHOWERS. THE GUIDANCE CONSENSUS SUPPORTED
CHANCE POPS TUESDAY NIGHT THROUGH THURSDAY...BUT BELOW 20 PERCENT
CHANCES FRIDAY AND SATURDAY. THE GFS...ECMWF...AND EKD MOS WERE
CONSISTENT WITH BELOW NORMAL TEMPERATURES THURSDAY THROUGH
SATURDAY.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
MVFR/IFR CIGS WILL CONTINUE THROUGH MID MORNING THEN IMPROVEMENT
EXPECTED.

CONVECTION ASSOCIATED WITH A PASSING SHORTWAVE IS RESULTING IN
STORMS AT CAE/CUB THROUGH 14Z WHILE OTHER TERMINALS SHOULD REMAIN
RAIN FREE...THOUGH ALL TERMINALS HAVE RESTRICTIONS. MVFR/IFR
STRATUS TO START THE PERIOD SHOULD IMPROVE TO VFR BY 15Z-16Z IN
THE WAKE OF THE PASSING SHORTWAVE WITH HEATING AND MIXING TAKING
PLACE.

SCATTERED CONVECTION EXPECTED TO DEVELOP DURING THE AFTERNOON IN
MOIST AND UNSTABLE AIR MASS WITH POSSIBLY A WEAK UPPER LEVEL
DISTURBANCE CROSSING THE REGION. SOUTH WINDS AROUND 10 KNOTS
EXPECTED THROUGH THE DAY.

EXTENDED AVIATION OUTLOOK...MVFR OR LOWER CIGS ARE POSSIBLE FOR A
FEW HOURS AT THE TERMINALS MONDAY THROUGH WEDNESDAY MORNINGS AS THE
LOW LEVEL MOISTURE REMAINS ACROSS THE AREA. OTHERWISE...SCATTERED
CONVECTION MAY CAUSE SOME BRIEF MVFR/IFR CONDITIONS EACH
AFTERNOON/EVENING THROUGH WEDNESDAY.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.

&&

$$
SYNOPSIS...99
NEAR TERM...99
SHORT TERM...99
LONG TERM...99
AVIATION...99



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