Scientific Forecaster Discussion
fxus62 kmlb 140115
Area forecast discussion
National Weather Service Melbourne Florida
815 PM EST Wed Nov 13 2019
NE winds continue to gust along the coast to 20-25mph this evng as a
strong high pres ridge centered over the Carolinas maintains a tight
sfc/low lvl pgrad acrs the Florida Peninsula. Frontal boundary stalled
over South Florida/Florida Keys is allowing high h100-h70 moisture to pool
within its trof with mean relative humidity values arnd 80pct over the Treasure
Coast and arnd 70pct over the space coast. Aloft, airmass is much
drier with 850 mb-h50 dewpoint depressions btwn 20-30c over the
Treasure Coast/lake-o region, and over 30c over the I-4 corridor.
The 14/00z kxmr/ktbw soundings reflect this well with a sharp
frontal-type inversion in the 850 mb-h70 lyr separating the two
vertically stacked air masses.
Mid/upr lvl steering flow east of the MS river has a strong zonal
component that will push the center of the high pres ridge off the
mid Atlc coast overnight. Sfc/low lvl winds will gradually shift
from NE to east and diminish thru late evng, but will maintain at least
5-10mph. The onshore flow will tap the high frontal moisture just
offshore that will maintain a moist and mild air advection pattern.
Such weather patterns generally produce brief coastal shras that have
little impact outside of -ra/dz and little in the way of quantitative precipitation forecast...this
one will be no different. Aftn fcst package handles this well with
highest pops over the Treasure Coast, diminishing northward with the
low lvl moisture gradient. Temp gradient will be arnd 15f acrs east
central Florida with mins bottoming out in the M/u50s along and north of
I-4, while holding in the u60s/l70s along the Treasure Coast.
Update sent arnd 00z to remove the beach hazard statement as it
expired...will update again arnd 03z once the high surf advisory
expires. No substantive changes necessary to the fcst.
Sfc winds: thru 14/05z...coastal sites NE 12-15kts with fqnt sfc g19-
23z...interior sites NE 8-12kts. Btwn 14/05z-14/08z...coastal sites
bcmg east/NE 7-11kts...interior sites bcmg east/NE 5-8kts. Btwn 14/13z-
14/16z...bcmg east 8-12kts...coastal sites ocnl sfc g18-22kts.
Vsbys/wx: thru 14/12z...btwn kmlb-ksua chc MVFR vsbys in -ra/br...
btwn kmlb-komn slgt chc MVFR vsbys in -ra. Btwn 14/12z-14/18z...
slgt chc MVFR vsbys in -shra all sites. Aft 14/18z...chc MVFR vsbys
in rain showers all sites.
Cigs: thru 14/06z...S of kism-ktix ocnl MVFR cigs btwn fl025-030...north
of kism-ktix VFR cigs btwn fl040-060. Aft 14/06z...VFR cigs btwn
fl040-060 all sites.
a fresh to strong NE breeze conts over the LCL Atlc as a high pres
ridge over the mid Atlc maintain a tight pgrad. Winds diminishing
overnight to a moderate to fresh easterly breeze as the ridge pushes
offshore and gradually weakens. However, the onshore breeze will
continue to high wind waves while pushing an easterly swell into the
east Florida coast. Seas 6-8ft nearshore and 8-10ft offshore. A Small
Craft Advisory remains in effect for all Atlc waters of east central
Florida...high surf advisory until 10 PM EST this evening for coastal
Volusia-Indian River-Martin-northern Brevard-southern
Am...Small Craft Advisory until 4 am EST Friday for Flagler Beach to
Volusia-Brevard County line 0-20 nm-Flagler Beach to
Volusia-Brevard County line 20-60 nm-Sebastian Inlet to
Jupiter Inlet 0-20 nm-Sebastian Inlet to Jupiter Inlet 20-
60 nm-Volusia-Brevard County line to Sebastian Inlet 0-20
nm-Volusia-Brevard County line to Sebastian Inlet 20-60 nm.