Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Pittsburgh PA
122 am EDT Tuesday Jul 7 2015
unsettled weather will continue through much of the week as a
cold front crosses Tuesday night and then stalls across the
Near term /through today/...
a weakening shortwave is prognosticated to gradually exit the region
tonight...though a few showers are expected to remain well S-east of
pit until then. Otherwise patchy clouds and some fog is expected
A cold front is prognosticated to approach the region Tuesday afternoon.
Warm middle levels are expected to limit instability somewhat. Shear
is not impressive either...but with some middle level dry air any
stronger storms could have gusty winds. Temperatures should
average a little above seasonal levels.
Short term /tonight through Thursday/...
the front will cross the region tomorrow night...bringing
widespread rainfall. As has been the case recently...the front
appears likely to stall out across the region. Latest models show
fairly good agreement that the front will stall across southern
portions of the forecast area Wednesday into Wednesday...but have
a bit more disagreement on Thursday. 12z NAM has the bulk of the
rainfall from Pittsburgh north into New York...while the 12z European model (ecmwf)
shows rainfall primarily south of Pittsburgh into Kentucky. Until
models come into better agreement...will simply keep chance probability of precipitation
for Thursday. With considerable cloud cover expected through the
period...temperatures should drop a few degrees below normal
Long term /Thursday night through Monday/...
frontal boundary will waver across the region through the period
as shortwaves move east in relatively zonal middle level flow. With
individual shortwaves hard to time have kept chance probability of precipitation through
the period. Temperatures close to wpc forecasts which seemed a good
Aviation /05z Tuesday through Saturday/...
scattered middle deck overnight with light south winds. An approaching cold
front will bring an increasing southwest wind over 10 kts middle
morning. Timing of front seems to be a bit slower with bulk of
showers or storms affecting ports from west to east after 23z.
Before then general VFR after any patchy morning fog lifts.
Outlook.../Tuesday night through Saturday/...
front will waver across region through the period with periodic