Flood Potential Outlook
Issued by NWS Buffalo, NY

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8
000
FGUS71 KBUF 062055
ESFBUF
NYC003-009-011-013-029-037-045-049-051-055-063-069-073-075-117-
121-132100-

Winter/Spring Flood Potential Outlook
National Weather Service Buffalo NY
355 PM EST Thu Feb 6 2020

...BELOW NORMAL FLOOD RISK THROUGH FEBRUARY 20TH...

This is the third flood potential outlook of the 2020 season. Flood
outlooks will be issued every two weeks into early spring to
summarize basin conditions and to assess the potential for flooding.
The outlooks are based on current and forecast hydrometeorological
conditions. This includes snow cover and water equivalent, creek and
river levels and the amount of ice on them, along with the expected
conditions during the next two weeks.

...CURRENT CONDITIONS SUMMARY...

Snow pack and snow water equivalent (SWE) are below normal.
Temperatures averaged 6 - 8 degrees above normal in January, which
resulted in more snow melt than typical for mid-winter. Also,
snowfall was below normal during the month, with these two factors
preventing much of a snow pack from getting established. For the
Buffalo Creeks, Genesee, Finger Lakes, and Allegheny basins the
majority of the snow pack in place is from snow which fell during
the past week. For these areas, SWE is only averaging about 50
percent of normal. There is a bit more snow pack in place across
the Black River Basin, where higher terrain maintained some
snowpack from January. Even so, SWE is still only about 65
percent of normal for this time of year.

The warm pattern has also limited ice development on the creeks.
There is very little ice on the Buffalo Creeks which are typically
vulnerable to ice jams. River and creek ice is also very limited
in the Genesee and Allegheny basins. There is a fair amount of
ice on the creeks and smaller rivers feeding into the Black River
basin, with mainly shore ice on the Black River itself.

The following is a summary of the conditions by basin as of Thursday
morning, February 6th:

...BUFFALO AREA CREEKS / LAKE ERIE BASIN...
.SNOW COVER..........3 to 6 inches lower terrain; 6 to 12
inches higher terrain.
.WATER EQUIVALENT....0.2 to 0.7 inch lower terrain; 1 to 2 inches
higher terrain.
.CREEK FLOWS.........Near to slightly above normal.
.CREEK ICE...........Mainly ice free.
.GROUND FROST........Less than an inch.
.GROUND STATE........Mainly thawed.

...GENESEE RIVER BASIN / FINGER LAKES / ROCHESTER AREA...
.SNOW COVER..........1 to 3 inches upper and lower Genesee Basin, 8
to 12 inches higher terrain of the middle Genesee Basin.
.WATER EQUIVALENT....0.5 to 1 inch.
.RIVER/CREEK FLOWS...Near to slightly above normal.
.RIVER/CREEK ICE.....Mainly ice free.
.GROUND FROST........Less than an inch across the lower Genesee
Basin...1 to 3 across the upper basin.
.GROUND STATE........Mainly thawed across the lower Genesee
Basin...mainly frozen across the upper basin.

...ALLEGHENY RIVER BASIN...
.SNOW COVER..........2 to 5 inches.
.WATER EQUIVALENT....0.25 to 1 inch
.RIVER/CREEK FLOWS...Near to slightly above normal.
.RIVER CREEK ICE.....Mainly ice free.
.GROUND FROST........3 inches or less.
.GROUND STATE........Mostly frozen...a few areas thawed.

...BLACK RIVER BASINS / TUG HILL...
.SNOW COVER..........6 to 12 inches, except 12 to 18 inches on the
Tug Hill and Adirondacks.
.WATER EQUIVALENT....1 to 2 inches, except 2 to 4 inches on the Tug
Hill and Adirondacks.
.RIVER/CREEK FLOWS...Near normal.
.RIVER/CREEK ICE.....Ice on the creeks and shore ice on the
Black River.
.GROUND FROST........5 to 9 inches.
.GROUND STATE........Frozen.

...TEMPERATURE AND PRECIPITATION OUTLOOK...

A storm system will bring a significant snowfall to the region
through Friday night, which will add to the snowpack in place. This
system will add 0.5 to 1.5 inches to the SWE already in place. This
will be followed by a period of below normal temperatures and mainly
dry weather over the weekend. This will be followed by a weaker
system which will bring about a quarter inch water equivalent of
either rain or snow Sunday night into Monday. This will be
followed by a couple days of mainly dry weather with near normal
temperatures.

Forecast confidence decreases later next week, with a wider spread
in model guidance. There is some indication that a much colder
pattern develop late next week, but this is far from a certainty.
However, even if this does not turn out, near normal temperatures
are not too much above freezing. Also, the pattern appears to be
a progressive one, featuring fast moving systems which are not
likely to produce heavy precipitation.

Looking further ahead, the latest Climate Prediction Center (CPC) 8
to 14 Day Outlook suggests that temperatures are likely to average
near normal, and precipitation slightly above normal. Climatologically,
this it is a cold time of the year so near normal temperature
would result in daytime highs averaging near to slightly below
freezing.

...FLOOD POTENTIAL OUTLOOK...

A cold pattern is expected for at least the next week. This
pattern will add to the snowpack in place, but it is unlikely to
result in a significant rain producing system.

There is a bit more uncertainly from late next week through
February 20th. Temperatures are expected to average near normal
during the period, which for this time of year would keep daytime
highs near freezing. It is difficult to completely rule out a
significant system this far out, but based on the expected pattern
the risk for a major rain producing system is low.

Taking these factors into account, the flood risk is below normal
through February 20th.

...ADDITIONAL INFORMATION...

Real time river information and probabilistic forecast for specific
locations along rivers across Western New York can be found on the
internet at www.weather.gov/buf. Since conditions can change, please
refer to the latest flood watches, warnings, and statements for
additional information.

Thank you to all the observers and agencies which have helped gather
data in support of this outlook. The next Winter/Spring Flood
Outlook will be issued on February 20th.

$$

Apffel



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.