April 25, 2008 08:12 am
—
By MARK HANOK
It looks like the extremely
dry weather pattern will continue
with a slight cooling
trend
In last week’s weather
column, I predicted that the
extremely dry weather pattern
would go on and on with
no end in sight. I explained
how an upside-down temperature
pattern is one of the
very best key indicators for
sunny, exceptionally dry
weather in Otsego County.
From Sunday afternoon,
April 13, through Wednesday
afternoon, April 23, there
wasn’t so much as a trace of
precipitation in our area, and
temperatures have averaged
15 to 20 degrees above normal.
This will be one of the
warmest April on record.
April is actually the most
likely month of the year for
“reverse temperature anomalies,”
and that’s because of
the Atlantic Ocean. Since the
ocean temperature is still
very cool in April, places
from the Virginia coast to
Long Island, New York City,
the lower Hudson Valley and
southern New England, can
be much cooler than central
and northern New York
whenever the wind is out of a
southerly, southeasterly, or
easterly direction. When low
pressure is cut off from the
jet stream, it can become stationary
offshore, and this
will enhance an east to
southeast flow, bringing
cooler air to the south while
there’s much more sunshine
and much warmer air to the
north. That’s exactly what
occurred this week, and since
the upside-down temperature
pattern has continued
for so long, it will be difficult
to break the cycle and get
much rain.
Although a cooling trend
is on the way for the upcoming
week, temperatures will
only get back to normal or a
few degrees above normal by
early next week.
On Friday, a major storm
system will track eastward
to the upper Midwest, and
bring showers and thunderstorms
eastward to the Ohio
Valley and wet snow north to
the northern Great Plains.
We’ll get a southwesterly
flow ahead of the low, so temperatures
will again be 15 to
20 degrees above normal,
with bright sunshine and
highs in the mid-70s.
The showers associated
with a cold front will try to
get here on Saturday, but the
front will weaken and a
blocking high to the east will
continue the dry weather
along the East Coast. Skies
will be partly sunny with
highs in the low 70s.
We may get a few showers
Saturday night and early
Sunday morning, but skies
will be partly sunny on Sunday
with a cooler northwesterly
flow; highs in the low
60’s will seem cool, but actually
that’s about five degrees
above normal for late April.
We’ll get another opportunity
for showers on Monday,
although skies will be partly
sunny with only the chance
of a shower, and highs
around 60 degrees.
Temperatures will finally
get closer to normal on Tuesday,
and after the chance of
showers in the morning,
skies will be partly sunny,
with highs from 52 to 57 degrees.
On Thursday, a large
storm in the middle of the
Atlantic Ocean blocked a
large high that extended
from Maine to the Florida
Panhandle. The atmosphere
went wild again, with practically
unheard of relative humidity
levels again in the
Southern Tier and Western
Catskills, between 10 and 15
percent.
A cold front in the upper
Midwest moved very slowly
eastward, blocked by the
high. Severe thunderstorms
developed from Iowa and
Missouri to north Texas. A
summer-like high pressure
area along the East Coast
moved very slowly eastward
on Friday, as a storm system
developed over the center of
the nation. A southwesterly
flow in between these weather
systems, and unlimited
sunshine, sent the mercury
soaring to 83 degrees at New
York City, 81 degrees at
Elmira, and 80 degrees at Albany.
The high was 77 degrees
at our weather station
in Otego.
Ahead of a cold front, severe
thunderstorms developed
across the Deep South.
With a northwesterly flow of
cooler air wrapping around
the low, the high was only 61
degrees at Little Rock, Ark.
and 65 degrees at Memphis.
At the same time, highs were
in the low 70s in North Dakota.
When it’s ten degrees
warmer in North Dakota and
16 degrees warmer in Elmira
than in Memphis, an already
extremely dry, sunny weather
pattern will be reinforced
in central and eastern New
York. For this reason, it was
a certainty that all the local
forecasts calling for cloudy
skies Sunday and Monday
would be completely wrong.
The upside-down temperature
pattern was so extreme
on Saturday that Syracuse,
where the high was 87 degrees,
ended up with the
highest temperature anywhere
in the nation except
for Arizona and Texas. That
kind of “reverse temperature
anomaly” reinforces extraordinary
dryness in the Cooperstown
area, where blazing
sunshine continued, and
the high was 84 degrees at
our weather station in Otego.
Low pressure tracked eastward
to near Chicago by late
afternoon, and its associated
cold front extended southward
to the Florida Panhandle.
On Sunday, the high was
82 degrees at Watertown,
while only 56 degrees in New
York City. When a “reverse
temperature anomaly” is this
extreme, very dry conditions
can continue for weeks in Otsego
County. A storm system,
completely cut off from
the jet stream, sliced southeastward
from the Ohio Valley
to North Carolina, while
high pressure backed southwestward
from the Canadian
Maritimes to eastern New
England. This is one of the
classic weather patterns for
upside-down temperatures,
and the more northerly locations
in New York were the
warmest places, while the
southernmost areas were the
coolest places. That’s because
there was bright sunshine
all day in northern New York
and along Lake Ontario,
while stratocumulus clouds
wrapped around the cut-off
low further to the south,
where the wind was off the
cool waters of the Atlantic
Ocean. In fact, low cloudiness
and a cool breeze kept
temperatures in the upper
50s in New York City.
Skies were partly to mostly
sunny in the Cooperstown
area, with highs in the low
70s.
The upside-down temperature
pattern became even
more extreme from central
and northern New York to
Virginia on Monday, as the
cut-off low and its associated
upper-level trough remained
nearly stationary over eastern
North Carolina. With
moderate to heavy rain for
much of the day in southeastern
Virginia, and a cool
easterly flow off the Atlantic
Ocean, the high was only 59
degrees at Norfolk.
At the same time, with
high pressure continuing to
back westward to northern
New England, brilliant sunshine
sent the mercury soaring
to 15 to 25 degrees above
normal from western, central,
and northern New York,
to northern Vermont. The
high was 78 degrees at Syracuse
and 77 degrees at Burlington,
Vt. It was just another
day of unlimited sunshine
in Otsego County, with a
high of 76 degrees at our
weather station in Otego,
and relative humidity as low
as 20 percent.
On Tuesday, Skies were
brilliantly sunny all day in
the Cooperstown area, with
highs in the upper 70s.
Mark Hanok is an Otegobased
meteorologist. You
can visit him on the World
Wide Web at http://members.
aol.com/weathergazette.
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