000
FXUS63 KBIS 301130
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
630 AM CDT WED JUL 30 2014

.UPDATE...
ISSUED AT 629 AM CDT WED JUL 30 2014

NO CHANGES TO THE DENSE FOG ADVISORY NEEDED AS OF 1130 UTC AS
VISIBILITIES OF ONE QUARTER MILE OR LESS ARE OF GREATEST COVERAGE
NORTH OF ND HIGHWAY 200.

UPDATE ISSUED AT 512 AM CDT WED JUL 30 2014

QUICK UPDATE TO ISSUE A DENSE FOG ADVISORY FOR NORTHERN NORTH
DAKOTA. WIDESPREAD VISIBILITIES OF LESS THAN ONE QUARTER MILE
WILL BE COMMON ALONG...NORTH...AND JUST SOUTH OF HIGHWAY 2 THROUGH
MID MORNING.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 255 AM CDT WED JUL 30 2014

A NORTHWEST FLOW WITH EMBEDDED SHORTWAVES WILL ONCE AGAIN
INVIGORATE THE NEED FOR AN ISOLATED SHOWER/THUNDERSTORM MENTION
TODAY. THE CHALLENGE WILL BE THE FAVORED LOCATIONS FOR THIS. HAVE
DECIDED TO POPULATE THE NORTHWEST THROUGH NORTH CENTRAL WITH
ISOLATED POPS...AND ALSO PORTIONS OF SOUTH CENTRAL.

FOR THE NEAR TERM EARLY THIS MORNING...PATCHY FOG CONTINUES TO
DEVELOP ACROSS CENTRAL NORTH DAKOTA AND WILL MAINTAIN THIS THROUGH
15Z.

LATEST WATER VAPOR IMAGERY SHOWS THE NEXT WELL DEFINED SHORTWAVE
JUST EAST OF PRINCE ALBERT SASKATCHEWAN...SLIDING SOUTH ALONG THE
SASKATCHEWAN AND MANITOBA BORDER. THE GFS SHOWS A REFLECTION OF
THIS IN THE 700MB-500MB VORTICITY LAYER. THIS IS FORECAST TO REACH
SOUTHWEST MANITOBA AND SOUTHERN SASKATCHEWAN BY 00Z THURSDAY.
NAM/GFS GUIDANCE/SOUNDINGS SHOW THE GREATEST INSTABILITY THIS
AFTERNOON RESIDING FROM KISN TO KMOT AND INTO THE TURTLE MOUNTAINS.
THIS IS IN LINE WITH THE SHORTWAVE TRAJECTORY. ADDITIONAL SHORTWAVES
PER GFS 700MB HEIGHT FIELD WILL BE APPROACHING SOUTH CENTRAL NORTH
DAKOTA BY 18Z TODAY. NAM/GFS SOUNDINGS SHOW WEAK INSTABILITY WITH
SUPPORT FROM THE HRRR AND ECMWF FOR ISOLATED SHOWERS/THUNDERSTORMS
THROUGH MID AFTERNOON. THUS HAVE OPTED TO FILL IN AN AREA ESSENTIALLY
FROM GARRISON TO BISMARCK..AND SOUTH TO THE BORDER WITH ISOLATED
SHOWERS/THUNDERSTORMS.

850MB TEMPS WARMING BY ANOTHER 1C TODAY WHICH WILL RESULT IN HIGHS
ABOUT 2 DEGREES WARMER THAN TUESDAY. THUS AFTERNOON HIGHS WILL
REACH THE UPPER 80S WEST TO THE LOWER 80S CENTRAL.

FOR WEDNESDAY NIGHT...FOLLOWED THE NAM WHICH MOVES A WARM FRONT
INTO NORTHEAST MONTANA AND WESTERN NORTH DAKOTA AFTER 06Z. LOW
LEVEL SOUTHERLY FLOW AND UPPER LEVEL NORTHERN FLOW WITH EMBEDDED
DISTURBANCES SHOULD BE ENOUGH TO GENERATE ISOLATED SHOWERS AND
THUNDERSTORMS NORTHWEST LATE WEDNESDAY NIGHT. OVERNIGHT LOWS
WEDNESDAY NIGHT WILL BE IN THE 50S.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 255 AM CDT WED JUL 30 2014

TEMPERATURES WARMING TO NEAR NORMAL VALUES THIS WEEKEND...TRENDING
SLIGHTLY BELOW NORMAL AGAIN EARLY NEXT WEEK HIGHLIGHT THE
EXTENDED FORECAST.

THE 00 UTC DETERMINISTIC AND ENSEMBLE SUITES ARE IN GOOD AGREEMENT
ON A HIGH AMPLITUDE RIDGE ACROSS THE ROCKIES THURSDAY SLOWLY
DE-AMPLIFYING INTO THE WEEKEND...WITH THE RESULTING BROADER RIDGE
AXIS SHIFTING ACROSS THE CENTRAL CONUS. THEREAFTER...THE UPPER
LEVEL PATTERN CONTINUES TO DE-AMPLIFY...BECOMING NEAR ZONAL MONDAY
AND TUESDAY. THIS PATTERN SUPPORTS A WARMING TREND TO NEAR
CLIMATOLOGICAL VALUES IN THE MID TO UPPER 80S BY
SATURDAY...COOLING INTO THE UPPER 70S TO LOWER 80S BY TUESDAY. IN
REGARDS TO CONVECTION...A CONSENSUS OF THE GLOBAL AND HIGH
RESOLUTION GUIDANCE SUGGESTS ISOLATED AFTERNOON STORMS ACROSS THE
SOUTHWEST THURSDAY. THEREAFTER...RIDGE RUNNING SHORTWAVES AND
IMPULSES EMBEDDED IN FORECAST ZONAL FLOW PROVIDE THE LARGE SCALE
SUPPORT FOR DIURNAL ISOLATED TO SCATTERED CONVECTION THIS WEEKEND
INTO EARLY NEXT WEEK.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 629 AM CDT WED JUL 30 2014

AREAS OF FOG WILL CONTINUE THROUGH 15Z WITH POSSIBLE MVFR TO A BRIEF
IFR VSBY AT KDIK/KISN. WILL MENTION VCFG AT THE REMAINING
TERMINALS. OTHERWISE EXPECT VFR CIGS/VSBYS WITH LIGHT WINDS NEXT
24HR. KISN/KMOT/KBIS WILL BE IN LINE FOR AN ISOLATED
SHOWER/THUNDERSTORM TODAY...BUT DUE TO THE SMALL AREAL COVERAGE
AND UNKNOWN TIMING...HAVE OPTED NOT TO MENTION ANY VCSH/VCTS UNTIL
SOMETHING DEFINITIVE DEVELOPS. AFTER 06Z THURSDAY...EXPECT A VCTS
AT KISN.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR NDZ001>005-
009>013-021>023.

&&

$$

UPDATE...AYD
SHORT TERM...KS
LONG TERM...AYD
AVIATION...AYD