Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Albany New York
153 am EDT Wednesday Jun 3 2015
high pressure over New York and New England today will slide
offshore Thursday bringing sunny seasonable weather. Late Thursday
into Friday a weather disturbance along the Carolina coast will
bring some clouds from the Catskills to southern ND New England.
Friday evening a cold front will drop south through the region
with scattered showers. Large high pressure will build over the
region for the weekend from Ontario with fair seasonable
Near term /through tonight/...
a large ridge of high pressure will drop south from Canada across
our region today allowing for pleasant conditions with moderating
temperatures and light winds. Temperatures should warm back to
near normal during the afternoon after a cool start to the day
with highs in the middle 60s to middle 70s.
High pressure will build off the New England coast tonight
resulting in clear and cool conditions with lows in the upper 30s
to upper 40s in most areas.
Short term /Thursday through Saturday night/...
NAM/GFS/Gem in agreement during this period...trending toward a
fair and dry solution for most of areas into Friday as surface high
pressure ridge from new eng SW into PA holds...and Carolina/Virginia cut
off remains south of most of our region. At 500 hpa just a fast
west-northwest flow with no sig short waves or other forcing. Carolina cut off
to our south Friday will spread clouds about as far north as the
i84 corridor. Isolated to scattered -shra may reach the southern tier of
counties...but from mhwk valley/Massachusetts north fair and dry conds should
persist into midday Friday. This solution on the coastal cut off and
its impacts is somewhat south of pvs runs...but is consistent
across the model suite.
Friday afternoon/evening a cold front will drop from northwest to southeast through the region. With
GFS base convective available potential energy around 200-300 j/kg and NAM which tends to be juicy
at most 500 j/kg...and Li 0 to -2 on both models will be mainly a
scattered -shra threat with isolated thunderstorm. GFS keeps all quantitative precipitation forecast north & west of
alb...NAM/Gem a tad more aggressive. At this time its at most a chance to
slght chance event.
After Friday evening large 500hpa cut off stays well north of region...as massive
surface high builds southeast from ont/qb into northeast for the weekend with
very dry airmass.
Temperatures will begin the period near to slightly above normal and end the
weekend slightly below normal...but otherwise a mostly Fair
Pleasant late Spring weekend.
Long term /Sunday through Tuesday/...
a low amplitude upper level meridional pattern will set across
the northern Continental U.S. With a series of low pressure perturbations
moving eastward along a 250 hpa 60-90 knots jet. 02/12z model output
has discrepancies with exact timing and quantitative precipitation forecast amounts with these
disturbances as some frontal boundaries may set up either over our
region or west of our region Monday afternoon into Monday evening
as a surface disturbance moves east and occlude over the
Ontario/Quebec border. Updates to the forecast will be made when
we get closer to this event. Southerly to southwesterly flow will
return to the region for Monday and Tuesday with temperatures
warming to slightly above normal with dewpoint temperatures
ranging from the middle 50s to near 60.
Aviation /06z Wednesday through Sunday/...
a mix of VFR/MVFR ceilings was observed and as the night
progresses...expectations are for additional stratus to evolve
with MVFR ceilings. For kpsf...better chance for IFR conditions due to
elevation. For the remainder of the Hudson Valley taf
locations...where partial clearing were to occur...so will the
increase probability for IFR conditions as we will place tempo
groups for the remainder of the overnight period.
Improvement will occur after sunrise Wednesday as drier air aloft
mixes down and VFR conditions will then continue through the end
of the taf period ending at 06z Thursday.
Winds will generally be light and variable through the taf period.
Wednesday night: no operational impact. No sig weather.
Thursday: no operational impact. No sig weather.
Thursday night: slight chance of rain showers.
Friday: moderate operational impact. Chance of rain showers...tsra.
Friday night: moderate operational impact. Chance of rain showers...tsra.
Saturday: no operational impact. Slight chance of rain showers...tsra.
Saturday night: no operational impact. No sig weather.
Sunday: no operational impact. No sig weather.
high pressure over southern Quebec will build southward into
northern New York and New England tonight...while a frontal boundary
stalls along the middle Atlantic coast. The high will bring gradually
clearing skies across our region tonight with continued cool
temperatures...then seasonably warm and sunny conditions for
Wednesday. The stalled front over the Middle Atlantic States will then
slowly drift northward by Thursday...bringing increasing clouds and
a chance of showers mainly to areas south of Albany.
Relative humidity values will rise to around 85 to 100 percent
tonight...decreasing to minimum values of between 30 and 40 percent
Wednesday afternoon. Relative humidity values will recover to around 80 to 100
percent Wednesday night.
Winds tonight will be northerly less than 5 miles per hour...becoming easterly
around 5 miles per hour on Wednesday. Winds will shift to the southeast around
5 miles per hour Wednesday night.
river levels will continue to recede as drier air filters into the
region tonight. The Still River at Brookfield has crested but will
remain above caution stage into tonight. All other rivers are below
caution stage. Dry conditions are expected through Thursday...with
a low probability for some showers Thursday night...and scattered
showers and thunderstorms Friday.
For details on specific area rivers and lakes...including observed
and forecast river stages and lake elevations...please visit the
advanced hydrologic prediction service /ahps/ graphs on our website.