kodiak_bull,
I resonate pretty closely with this forecast, though I don't believe the NAO or cold will break anytime soon. Note the potential for major storms; if you don't want to read all the weatherese, scroll down to the bolded (my emphasis) near the end of article:
accuweather.com
MONDAY, DEC 11, 2000
TROPICAL DISTURBANCE CHAD SOAKS SOUTH FLORIDA AS
TEXAS BRACES FOR WORST WINTER STORM IN 20 YEARS
STATEWIDE.
I do not remember seeing a map like this in all my years I have watched
the weather. Say what you want about what happened in South Florida
yesterday, but that was the low to mid-level system that came out of the
Caribbean (which for fun we dubbed Chad) and is just to the west of
West Palm Beach this morning. Rain amounts for a December system
were nothing short of phenomenal with 5-10 inches in coastal Dade and
Broward and even 15 inches at Homestead. Only a system of deep
tropical origin could have done that at this time of the year. Doctor Joe
Sobel told me that before the game the weathercaster on FOX (which by
the way is my favorite network, so I am not taking a potshot at them
because I don't like them) said that Miami would have their usual
10-minute shower at 3 o'clock. Hmmm. In any case, that system should
weaken out to sea today, but serves as a reminder that the southwest
Atlantic ridge is alive and well, and if not for cross-polar flow and a
negative NAO, it would be balmy all in much of the nation east of the
Mississippi not only today, but much of this week. But alas, that ridge,
after trying to resist this week, will be forced to start backing off next
week and by Christmas should be overwhelmed and forced to near 60
west as a classic Pacific-North American telleconnection sets up and
establishes the Polar Vortex on the west shore of Hudson Bay with a
ridge near or just off the West coast. The depth of the cold that
overwhelms the nation will be something that we will have to handle with
each different air mass that gets caught in the flow, for there is a chance
the tremendous cross-polar stream could get dammed a bit, and that
means the pattern would not be as cold as if it did not. This is what
happened last Christmas week, but with the way things have been going
this winter, I would not bet on it. Remember, the 6- to 10-day forecasts
for the Northeast for this week had all forecasted warmer than average
(amazingly yesterday still has warmer than average for the Northeast and
average in the 8- to 14-day period). If it happens, it will have to take a
pattern reversal and be the first correct one issued for any warm period. It
continues to astound me how little attention is paid to source regions of air
masses and how much is paid to mean 500 mb flow. Forecasters in the
50s and 60s in this pattern would have a field day cleaning the clocks of
the model interpreters.
This week is a classic example. The very cold air mass in the Plains is
plummeting southward and when this week is done, it will take a miracle
for Texas to average out above normal for December. It may be one of
the coldest 45- to 50-day periods in November to December in 50 years
in the Lone Star State when it's all said and done, yet such an extreme
deviation was only forecasted in the strong analogs to cold in the southern
Plains outlined in the winter forecast we put out. (Please read our winter
discussion about this idea.) Of course, there is still time to change, and
one may argue that it can't get any colder than this. Dallas by the 20th may
have a 50-day deviation of -6.5, given the intensity of the current cold
shot and the next one the European has. This can't go on forever down
there as the rubber band has to snap sometime. It is fortunate for the
Deep South like Texas that this was not a December/January pattern.
That being said, the ducks are on the pond for one of the most
widespread ice/snow events in the last 50 years in Texas. The storm
developing over Arkansas now will hightail east-northeast to near
Watertown, N.Y., tomorrow morning, then into the Maritimes tomorrow
night. A wind-whipped blizzard will develop north of its path including
Chicago where 4-8 inches of snow will fall. Amounts could reach a foot in
areas of southwest Michigan, where the lake is involved. The cold front
will drop southward to Brownsville by this time Tuesday and then to
Tampico by Wednesday. A strong subtropical disturbance will move into
Mexico tomorrow and initiate low pressure development in the western
Gulf. By this time, all of the Lone Star State, except for maybe the Gulf
coast, will be at or below 32 and because of this we are liable to have a
major icing event all the way to Houston and San Antonio with lesser
amounts further south. Further north a change to sleet will occur, then
snow northwest of Dallas to Midland line, where large areas of 2-4 inches
will accumulate with a local amounts to 8. This beast will start northeast
Wednesday.
The question is will it stay a beast. I think a formidable area of
precipitation will ride northeast and will have snow on its northwest side,
and the cards are on the table for major icing continuing through
Tennessee with a cold rain further south. The ducks are on the pond for a
severe ice event from the upstate of South Carolina and northern Georgia
through Virginia and snows of 3-6 inches in the I-95 corridor from
Washington northeast. All this assumes that the wave flattens coming into
strong confluence caused by the fight between the negative NAO and the
blossoming southwest Atlantic ridge. The model idea that this short wave
squeezes out rapidly appears right since the flow ahead of it will be very
fast. The fly in the ointment, though, is the idea of it being slower and
allowing the vigorous upper storm now west of Oregon to catch up and
phase. This would allow a stronger storm come up further west of the
mountains with a big development along the mid-Atlantic coast early
Thursday. This is what the models had a couple of days ago initially and
they may go back to it. This would not get the Carolinas and Virginia out
of their low-level cold air icing predicament, but would mean heavier
snow further north and the change to ice or rain in the I-95 corridor. The
answer will not become clear until Wednesday when we see what the
chances of phasing are. With such a strong temperature difference, one
does not need a big storm to produce heavy amounts of precipitation. In
fact, for much of Texas, pressures will be high while they suffer their
attack of the arctic hound. This will not be a serious threat to citrus down
there as the lowest temperatures may be 28-32 while it's raining. This will
be a miserable storm for humans, though, as almost all the state will suffer
from some kind of harsh winter elements. Further north and east, this will
be a pain in the neck all the way to New England, though the verdict is out
as to whether it will just be a flat, fast wave that produces a lot of
precipitation (remember the Christmas storm two winters ago that
produced the snow and ice in a "warm" pattern) or a bigger storm if we
see some kind of phasing.
Before we move on, the current storm is liable to really be a head-turner
not only for its snow, but wind south of the path when the cold air rushes
in tomorrow. In fact, I would make sure the hatches are battened down
from the Mason-Dixon Line northward as 50-mph winds are possible
tomorrow midday and afternoon once the front is through.
If you get to your accuweather.com southeast Pacific cloud photo, you
can easily see why this trough never dug into the west. As long as we have
some kind of trough east of Hawaii, arctic air can't come into California. It
can, though, get into the Pacific Northwest, and we have a potentially
interesting storm coming up later this week for Washington and Oregon.
A strong disturbance will come ashore in northern California Wednesday
night. By the way, the slower this moves, the better the chance the system
in the East will deepen. In any case, enough cold air may drain southwest
so coastal Oregon may have snow Wednesday night into Thursday. This
system will be in the Plains Friday, then lift northeast into the lakes
Saturday, allowing another day or two of warmer air to try to spread
back into Texas, and then the Ohio Valley and the East. But this morning's
run of the European says that the trough merely supplies the height full
center for the strong arctic jet to aim at, and by Saturday morning an
arctic high of 31.00 inches will be in Montana. The arctic front will reach
the East Coast Sunday, a morning which may have South Texas even
colder than what this outbreak will bring, since precipitation as the upper
flow goes northwest. I am concerned that this system may try to have a
wave on it as it appears this will be the system that starts a transition from
the current pattern to one known as the Pacific North American
telleconnection. In any case, with that trough east of Hawaii and
progression starting, the whole weight of the cold air may come. The
pattern next week and the week after is one that will lead to strong digging
troughs from the arctic branch, many of them dry, but some of them that
can get so far south that they breed storms. Something to think about for
dreamers of a white Christmas.
Water temperatures in the north Atlantic are starting to cool now, so the
effect of that warm water may lessen as the winter goes on. This means
the strong negative NAO that has been so prominent the last several
months will weaken, leading to less predictability of the pattern. It is
interesting to note that the influx of very cold arctic air via cross-polar flow
has essentially ruined the warming that should have occurred in much of
the East this week. The realization that this would happen became plainly
apparent last week and ruined the speculation from mid-November on my
part that the 3rd through the 15th would be warmer than average in the
East. Such things, such as the actual influx of true arctic air masses into
North America are not obvious, though, until a week away, so while it
wrecked a 3-week sensible weather forecast (we did hit the ridging that
was occurring), it certainly did destroy the models from last week which
were forecasting the polar vortex in the West this week and several days
of 50-plus in the Northeast. Keep in mind, the effect of the NAO is to
build the road it rides to its own death as deeper storms over that warm
water will cause the upwelling to cool it. By the time it disappears, though,
the combination of variations to patterns may be showing up 2 weeks
down the road that we are seeing this morning, and the fact that it will take
all winter to snap us out of the old pattern may make it too late for the
nation not to take a massive hit on fuel bills. In other words, this cold start
is not likely to reverse to very warm like 1989-1990, but instead to, at
warmest, a normal to slightly above east of the Mississippi and at worst
remain cold with occasional warm variations of the pattern if the NAO
goes positive from time to time.
In think I have Carpal tunnel syndrome from all this.
Ciao for now. |
