418
FXUS02 KWBC 041812
PMDEPD
EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
212 PM EDT FRI JUL 04 2008
VALID 12Z MON JUL 07 2008 - 12Z FRI JUL 11 2008
INCLINATION FOR THE PRELIMINARY FRONTS AND PRESSURES FOR THE
MEDIUM RANGE IS TO STAY AWAY FROM ANY AGGRESSIVELY DEEP TROUGHS
ALONG THE COMMON BORDER OF THE UNITED STATES AND CANADA...A LEAN
TOWARDS MIDSUMMER CLIMATOLOGY. JUST WHERE THE POLAR JET WILL
BUCKLE IS CONTENTIOUS...WITH THE 00Z ECMWF OUT OF SYNC WITH THE
OTHER DETERMINISTIC MODELS...AND LITTLE COMMON GROUND BETWEEN THE
00Z GEFS MEAN AND THE 12Z/03 ECMWF ENSEMBLE MEAN. THE 00Z/04
ECMWF ENSEMBLE MEAN APPEARS TO BE AS GOOD A COMPROMISE AS ANY
BLENDED WITH THE GFS ENS MEAN...ALL RECENT GUIDANCE
CONSIDERED...SO IT WILL FORM THE BASIS OF THE FIRST DRAFT OF THE
MANUAL CHARTS FOR MUCH OF THE PERIOD. BOTH THE 00Z ECMWF AND GEM
GLOBAL MODELS ARE MORE VIGOROUS THAN THE GFS AND UKMET WITH THE
SHORT WAVE ENERGY OVER TEXAS AT THE GET GO DAY 3...BUT DO NOT HAVE
A GOOD HANDLE ON THE MERIT OF LEANING ONE WAY OR ANY WITH THAT
DISTURBANCE. WHATEVER THE CASE...THE SURFACE PRESSURE REFLECTION
IS MINIMAL...WITH THE PROBLEM BEING HOW MUCH RAINFALL MAY OCCUR
OVER THE SRN TEXAS.
LATEST 12 GFS TRENDING TOWARDS THE 00Z ECMWF OVER THE EPAC AND PAC
NW WITH MORE RIDGING DAYS 4-7. THIS RESULTS IN A MORE DOWNSTREAM
ERN CONUS TROF LATE WEEK. PREFER TO CONT TO USE THE ECMWF ENS
MEANS WHICH REFLECT THE HIGHER NWRN CONUS HTS BUT DOWNSTREAM
AMPLITUDE IS QUITE UNCERTAIN AND A MORE BROADLY ZONAL FLOW
PREFERRED AT THIS TIME RANGE.
TS BERTHA TO TRACK NWWD OVER THE NEXT 7 DAYS REMAINING WELL
SEAWARD OF CONUS. VERY LARGE TRACK SPREAD SHOWING UP IN GLOBAL AND
HURRICANE GUIDANCE RUNS AFTER DAY 5. HPC/NHC COORDINATION
RELECTING A MORE SOUTH AND WWD SHIFT OF SEVERAL GLOBAL MODELS.
LONGER TERM UPSTREAM MID LEVEL PATTERN OVER CONUS UNCERTAIN WITH
POOR CONTINUITY OF RECENT RUNS. PREFERENCE OF A MEAN WRN CONUS
TROF AND W ATLC/SERN CONUS RIDGING REMAINS SIMILAR TO ECMWF AND
GFS ENS MEANS.
CISCO/ROSENSTEIN
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page