Winter Outlook 1999-2000
Posted: November 29-2:00PM
The winter of 1998-1999 was one which featured a relatively
mild overall pattern in our neck of the woods with little
significant snowfall aside from a couple of snow to ice to
rain situations. The pattern so far this fall has been somewhat
similair to last year's pattern in terms of the above normal
temperatures that much of the nation has seen thus far. One
factor which is being studied is the effect that La Nina has
had on past winters in the United States. La Nina is the
cooling of the equatorial waters in the Pacific Ocean. Once again, we
find ourselves in a La Nina pattern, however, not quite as
strong as we saw last year. So, what effect will La Nina
play in our weather this winter? It's hard to say. La Nina
and El Nino are still misunderstood and haven't been researched
quite enough to put a stamp on how it will affect us from
season to season. As I said, there are similarities thus far in
comparison to last fall at this time. For instance, the
core of true Arctic air has basically set up shop over
Siberia and Northern Europe while on the other side of
the world(U.S.), a fairly tranquil fall has been seen
with a large ridge in place over the center of the nation in
late October and early November.
In recent weeks, this ridge has shifted east and caused above
normal temperatures in the middle part of November. It
appears as though the atmosphere is changing in two-week
cycles. One period has seen a ridge in the center of the nation
with troughs on both coasts. After the pattern shift, the
pattern reverses with a trough in the midsection, a weak ridge on
the west coast, and a southeasterly ridge in the east. Expect
this southeast ridge to strengthen a bit later in December
as is often the case in a La Nina year.
Another similarity between the pattern last year and so
far this year is the amount of warmth that still hasn't been
eroded over parts of Texas and the Gulf states region. It
strikes me that we had Hurricane Mitch last year, a strong
Category five hurricane, and Hurricane Lenny this year, which
were both November hurricanes. Case in point, cold fronts
earlier this fall (October-early November) struggled to make it all the
way to the Gulf coast, except for one instance in early
October when an early season cold shot sent a true
Blue Norther into Texas. Simply put, the flow aloft was
conducive enough to induce tropical development.
Well, I tried to keep my thoughts
as simple as possible. There are still many more factors
which I didn't mention as to my outlook for this upcoming
winter. One trend that I feel will be with us for a while
is a strom track from Texas/Gulf states into the Great Lakes.
This doesn't mean that we won't see our share of coastal
lows taking over this year.
We have already seen a few recent storms in middle-late
November track through the Great Lakes and notably, none have
caused much in the way of wintry weather. This is yet another
sign that the core of cA lies on the other side of the world.
However, this cold air mass is showing signs of moving. If
it should slide over into Alaska and western Canada, the
"Great Lake storm track" most definitely will shift.
So what does this all mean? Early December should see the
pattern begin to buckle with the coldest temperature
values slowly shifting to Alaska and western
Canada. A storm track through the Great Lakes should
still prevail during this period, but by mid-December,
true Arctic air may make it's first trip to the lower
forty-eight and may decide to stick around for a little
while. Later in December, a ridge over the southest should
strengthen causing any cold shots in the mid-Atlantic and
southeast to be short-lived. Again, the pattern seems to be
on two week cycles, so expect fairly quick swings in the
weather from cold -> mild and from dry -> stormy. The core
of the winter (mid-January/mid-February) will average near
normal as far as temperatures but expect some very
cold periods as the cA will make several dives for the Northeast.
In turn, since I do feel temperatures will be near average,
expect the coldest days to be balanced out by unseasonably
mild days as well. As we head into the latter stages of
winter (late February/late March) expect a wild ride.
Temperatures will average above normal in our area, but
expect drastic swings in the weather. This is the period
where I expect to see more coastal lows forming, but a
slightly inland track will spell rain for the majority of
the storms. However, I feel at least one snowstorm will
be in order as the pattern goes through it's "setting-up"
stage for the spring.
All in all, this winter looks to be slightly colder than
last year with a storm track even farther west for some of
the season. Our
coldest period (in terms of daytime highs) will occur from
mid-January to mid-February. The period with the most
activity and fluctuation in temperature and storm
track will be from mid-February to mid-March. Granted,
this is not etched in stone and is just my outlook
based on past and present trends.
