Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Albany New York
338 PM EDT sun Oct 4 2015
high pressure will provide fair and dry weather into the middle
week. Some locations outside of the capital district and middle
Hudson Valley will have some areas of frost tonight. Temperatures
will moderate to slightly above normal readings by Tuesday into
Wednesday with the next threat of rainfall by Friday.
Near term /through tonight/...
as of 330 PM EDT...water vapor loop along with hourly rap updated
guidance reveals a building upper level ridge across New England.
There is moisture coming in off the Atlantic into the middle Atlantic
region while another plume of moisture was advancing northward
across the Tennessee and Ohio valleys into western New York.
Meanwhile...surface ridge across northern Quebec will continue to
extend its influence further south overnight which should continue
the trends of clearing skies and diminishing winds. As mentioned
in the previous excellent forecast discussion...ideal near
radiational cooling should commence for temperatures to drop back
into the 30s to around 40f from Albany and points southward. No
changes to current headlines or temperatures overnight.
Short term /Monday through Tuesday night/...
The remainder of the short term is expected to continue tranquil
with a return toward seasonable temperatures. Guidance numbers are
rather close and very close to previous excellent forecast grids
so little enhancements were included in this forecast package.
Still some question how much Atlantic moisture advects into our
western New England counties and moisture across the Great Lakes
region advects eastward across the region Monday night into
Tuesday. Relative humidity values within the NCEP model suite and international
guidance still point toward rather high values within the h850-700
layer advecting into eastern New York Monday evening then across most of
the County warning forecast area into Tuesday morning. This is primarily along the thermal
trough axis as we will increase cloud coverage percentage which
will still spell out partly cloudy for the most part. Conditions
improve Tuesday night.
Long term /Wednesday through Sunday/...
with the departure of Joaquin and the associated anomalously deep
southern trough to our east...a more normal zonal flow will become
established across the Continental U.S. At least into the weekend.
By the weekend...there is some disparity among the long term models
regarding the overall tele-connection. The GFS and Canadian hint of
ridging along the eastern Seaboard...while the European model (ecmwf) indicated a
trough beginning to build on the eastern Seaboard as ridge develops
in the central portion of the Continental U.S..
So confidence starts high in the beginning of the extended...falling
to at least moderate as we head into the weekend.
The forecast opens up on Wednesday with high pressure building
southward from southern Canada to bring another round of dry weather
with near seasonable temperatures. Dry weather with sunshine looks
to continue into Thursday.
By Friday...a disturbance including some sort of low center and a
cold front...will approach from the southern Great Lakes. The
European forecasted the deepest low pressure area...while the
Canadian offered the weakest and slowest solution (a much less deep
low pressure center)...not reaching our region until Saturday. The
12z GFS was in the middle regarding the low pressure depth...but
faster like the European model (ecmwf).
For now...we will include mainly chance probability of precipitation across the region for
Friday...with likely probability of precipitation across the Adirondacks where better
forcing and and upslope lift will enhance the chance for showers.
This system should move south and eastward on Saturday...but with
the difference forecast solutions (the Canadian much slower and
implying showers on saturday)...we went with slight probability of precipitation for
Saturday into Saturday night.
If the 12z GFS is correct...more moisture could begin to be pooled
northward from the Gulf of Mexico as early as next Sunday. At the
same time...another cold front will be slipping southward from
The European model (ecmwf) has a northwesterly flow setting up over the region by
Sunday (again with a trough building further downstream along the
eastern seaboard). This would imply a mainly dry solution but still
there is a cold front in southern forecast pushing into the
Since both models suggest some possible light precipitation with the
cold front will have chance probability of precipitation in our northern areas next
Sunday...with only slight chances from the capital region southward.
Temperatures through the extended looks pretty spot on to
climatological averages. This will mean high temperatures averaging
from the upper 50s northwest to the upper 60s southeast through the
about Saturday...cooling a bit next Sunday to the highs in the lower
50s across our Adirondacks...to lower 60s in southern zones.
Overnight lows will generally average from the upper 30s across our
northern areas...to the upper 40s across our southern areas
throughout the extended period.
Aviation /19z Sunday through Friday/...
high pressure over eastern Quebec will continue to build across
southern Canada through the taf period ending at 18z Monday. As a
result mainly sky clear conditions are expected at the taf sites with
VFR conditions and only some thin high clouds and scattered
stratocumulus from time to time.
Winds will be north-NE at 6-10 kts during the remainder of the
afternoon becoming light and variable tonight and then north-NE at
4-5 kts Monday morning.
Monday nt-Thursday nt: no operational impact. No sig weather.
Friday: moderate operational impact. Chance of rain showers.
dry conditions continue into the middle week period for all of
eastern New York and western NE.
Fire weather related concerns remain very low at this time.
Recent wet conditions earlier in the week...and especially south
of the capital region late Friday into Saturday...along with
higher than average relative humidities and diminishing winds
should allow for minimal fire weather issues.
Relative humidity values will recover to between 90 and near 100
percent tonight with areas of frost and dew. Minimum relative humidity values of
35 to 50 percent can be expected Monday afternoon.
Winds will become light to calm tonight. Light and variable in
direction winds of 5 miles per hour or less will be likely on Monday.
no Hydro problems are expected the next 5 days in the Albany Hydro
Dry weather is expected through Thursday...with the next chance
of rainfall on Friday. Flows will continue to lower to seasonal
levels from the heavier rainfall earlier in the week.
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
kenx radar is out of service until further notice due to a
New York...frost advisory from midnight tonight to 9 am EDT Monday for
Freeze warning from midnight tonight to 9 am EDT Monday for
Massachusetts...frost advisory from midnight tonight to 9 am EDT Monday for
Vermont...frost advisory from midnight tonight to 9 am EDT Monday for