North Atlantic Marine Weather Discussion

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AGNT40 KWNM 241935
MIMATN

Marine Weather Discussion for N Atlantic Ocean
NWS Ocean Prediction Center Washington DC
335 PM EDT Sun Jun 24 2018

.FORECAST DISCUSSION...Major features/winds/seas/significant 
.weather for the North Atlantic Ocean W of 50W from 30N to 50N.

Current Conditions...The 12z surface analysis shows a cold front
extending across the southern nt1 waters, then becoming a
stationary front near the Cape May region. The analysis also 
shows a low pressure trough approaching the mid Atlantic coast 
from the W, with high pressure ridging over the SE part of the 
nt2 area. The fronts are combining with the ridge to produce 
brisk SW flow over the northern and central nt2 waters S and E of
1000 fathoms. Latest available ascat and ascat hi-res passes 
from a few hours show 20 to 30 kt across the northern/central 
outer nt2 zones, 15 to 20 kt winds over the inner zones off the 
Carolina coast, and 5 to 15 kt winds elsewhere across the 
remaining offshore waters. Lightning density product data at 
1850z shows a line of scattered showers and tstms just S of the
cold front, which extends NE to SW across the northern nt2 
waters. The lightning density product also shows scattered
showers and isolated tstms over the outer southern nt2 waters.

Models/Forecast...The 12z medium range models are in very good 
overall agreement across the offshore waters through Fri night,
except the models have fallen into two opposing camps regarding a
low that is expected to form near the South Carolina coast Tue
night, with the 12z ecmwf/cmc taking the low NE across the
offshore waters Wed through Fri while strengthening it
significantly but the 12z gfs/ukmet keeping the low near the
Carolina coast as a weak system. For now will use the 12z gfs 
10m/30m solution with the stability smart tool for the wind 
grids through the forecast period, since it looks like a
representative model solution that provides continuity with the
previous grids. Am not planning to make any significant changes 
to the current forecast trend at this time.

Seas...The 12z wna wavewatch and 12z ecmwf wam both initialized 
well over the coastal and offshore waters versus the latest buoy 
observations and altimeter data. The models are good agreemnt for
tonight through Tue, then diverge starting Tue night as the
atmospheric models start to show noticeable differences. The 12z
wna wavewatch will be used over the entire forecast period, in
order to be consistent with the preferred 12z gfs wind grids.

Extratropical Storm Surge Guidance...N/A.

.WARNINGS...Preliminary.

.NT1 New England Waters...
     None.

.NT2 Mid-Atlantic Waters...
     None.

$$

.Forecaster Scovil. Ocean Prediction Center.