The latest storm in what already has been an incredibly active winter season out East is headed for the major cities of the Mid Atlantic–including Washington, Baltimore, Philadelphia and possibly at least sections of the New York metropolitan area later Friday–while threatening Chicago with a period of snow and a weekend of chilly, lake-driven snow showers. The mammoth system is only to graze the Chicago area–reserving its fiercest blow for the mid-Atlantic where blizzard conditions are likely to evolve, driven by 40 mph gusts. Coastal areas such as Atlantic City, may well see white-out conditions brought on by winds as high as 50+ mph.
While a bit of drizzle or freezing drizzle possibly mixed with some ice pellets or a few flakes of snow flirt with Chicago Friday morning, a steadier period of snow is slated to arrive here later this afternoon and Friday night. An inch or more of snow has fallen on only 3 calendar days since Jan. 1. The incoming snow could lay down 1-3 inches of snow over sections of the Chicago area, becomingthe 4th one-inch-plus snow event of 2010.
Snow is predicted to be falling vigorously by mid and late afternoon Friday in Washington D.C. That city already has a 2009-10 seasonal snow tally of 31.1 inches– three times the normal of 12.4 inches to date. Remarkably, only 2 inches had fallen there by this time a year ago. The current season’s snowfall—even in advance of the incoming storm—amounts to more than ALL the snow recorded across the District in the last 3 seasons combined.
As much as 16 to 24 inches of snow is predicted to fall there in the latest storm amid howling winds—and a foot or more of snow appears a good bet in Baltimore and Philadelphia as well. Effects of the storm are likely to be felt in those cities well into Saturday—though the heaviest falling snow is to begin winding down midday tomorrow.
Gusty, cold weekend winds to activate the lake snow machine
The storm’s impact on Chicago’s weather is expected to be far less radical. But the process of intensification—known as “cyclogenesis”— will encourage air to rush into the system from its periphery, a set-up which is to manifest itself in the strengthening east to northeast winds likely to race through Chicago Friday. Gusts to 30 mph are possible by and during Friday night.
Lake-effect snow showers hit Saturday/Saturday night
Winds will blow from a northeast direction Friday night into morning then become more northerly. It’s a change which will increase the distance cold air travels over lake waters before reaching Chicago Saturday, raising the possibility initially light and scattered bursts of lake-effect flurries in the morning may increase to better-organized snow showers later in the day into Saturday afternoon and night.
Potent system bearing some similarities to the early January snow-maker here being monitored next week
A second, potentially more significant snow-maker may threaten the Chicago area area Monday night into Tuesday. The southeast-bound disturbance, predicted to dive from Manitoba Canada into Missouri Monday then track across Illinois. It’s a development which could put Chicago in a strong region of “atmospheric lift” Tuesday setting the stage for snow.
January and February are the two coldest months in Chicago. Which months are in third place, fourth, fifth, etc.?
Here are the months and their average temperatures, ranked from coldest to warmest: January, 24.3 degrees; February, 27.9; December, 28.9; March, 37.7; November, 40.8; April, 49.6; October, 54.5; May, 60.3; September, 66.1; June, 70.5; August, 73.7; and July, 75.2.
We used Midway Airport data from 1929 to 2009 to generate those averages. Although monthly average temperatures are slightly different at other locations in metropolitan Chicago, the ranked order remains the same.
The ranking by season is winter (December through February), 27.0 degrees; spring (March through May), 49.2; autumn (September through November), 53.8; summer (June through August), 73.2. The first half of the year (January through June) averages 45.1degrees and the second half (July through December), 56.6.
How are things in your part of the troposphere? The troposphere is the lowest layer of the atmosphere where we live and most weather occurs. Scientists are now finding El Nino’s influence on our weather isn’t just limited to the troposphere but also effects the stratosphere.
El Nino, the warming of the eastern Pacific ocean near the equator, has far reaching effects on global weather patterns. We have seen those effects this winter with heavier than normal precipitation in the south. Yet another storm will swipe the southern plains with snow today and tomorrow before deepening over the mid-Atlantic where numerous winter storm watches and warnings are posted. Nearly a foot of snow could fall on the Nation’s Capitol where they have already seen more than twice the normal snowfall this winter.
If all the atmospheric chips fall into place in just the right way over the next week, the Chicago metro area could rack up snow tallies larger than the 4.5 inches of snow which fell all of last February. But the onset of snow isn’t likely to occur until Friday–comparatively mild air is in the cards first. Thursday afternoon may host Chicago’s mildest official high of the past 11 days.
Readings Wednesday hit 33-degrees at Midway Airport, 35 at the lakefront and 32 at O’Hare. The 36-degree official reading predicted for O’Hare Thursday afternoon would be the area’s mildest since a 46-degree high on Jan. 24–nearly two weeks ago.
All is far from sanguine in the world of U.S. weather. A major storm is again under development–this time in the southern Plains. It’s the first of two expected to come together in the next 7 days. The latest system has prompted the issuance of an array of winter storm watches and advisories across sections of 23 states–extending from New Mexico and the Texas Panhandle all the way to the East Coast near Washington, D.C. The developing system is behind a series of gully-washing (and thundery) downpours which drenched south Texas Wednesday. Fredericksburg –northwest of San Antonio–measured 2.64 inches of rain while San Antonio proper logged a 2.50 inches daytime tally. Big snows on the storm’s cold northwest side buried the mountains of New Mexico near Albuquerque with as much 8 inches of snow.
The storm is to move from Gulf Coast waters east of Texas northeastward toward the South Carolina coast. It arrives there Friday afternoon then explosively deepens once in contact with western Atlantic waters east of North Carolina. It’s at that point snowfall and winds should begin increasing rapidly across sections of the mid-Atlantic—including Washington, Baltimore and Philadelphia.
With the 2009-10 snow tally in Washington, D.C. now up to 31.1 inches—nearly 16 times the 2 inches which had fallen by this time a year ago and more than ALL the snow which has fallen there the past three seasons combined–another major winter storm is not what East Coast residents need. The books closed on the region’s last storm only earlier this week.
Providing the storm remains on the track now projected for it, a foot of snow could fall on the Nation’s Capitol by Saturday. The strong winds on its north side are likely to buffet Chicago as well, strengthening slowly Friday and gusting to 30 mph at times Friday night and Saturday.
Estimates of how much snow the southern storm may produce here between Friday afternoon and Saturday night range on various computer models from 2 to as much as 5 inches–with possible lake-enhancement. These are preliminary figures which will be updated. Precipitation here may begin late Thursday night as a bit of drizzle, freezing drizzle, sleet or flurries likely to increase in intensity Friday afternoon and evening.
Rare mid-winter Air Pollution Action Day declared by Illinois EPA
It’s not often an Air Pollution Action Day is declared in winter–but it happened Wednesday and extends through Thursday. A pollutant-trapping temperature inversion above Chicago, which in combination with light winds, has shut down the mixing of air which typically thins pollution concentrations, continues in place. Stronger winds will begin taking hold as the latest storms passes to the south bringing the pollution episode to an end.