A February snowfall of 10" or more occurs on average only once every 16 years in Chicago. Only five such storms are on the books at Midway Airport in the 81 years since 1929. Tuesday's storm may well become the sixth! Before it finishes with the Chicago area, 8 to 14 inches of snow may accumulate--the season's heaviest to date and the biggest storm to occur here since nearly a foot fell here over two days just over a year ago in late January
The current system's impact on the Chicago area is only in its early stages as Tuesday gets underway. Three rush hours may ultimately be impacted by the system--none more than Tuesday evening's when snowfall will be at its height and winds will be gusting to 25 mph--strong enough to begin sending the additional 4 to 7" of snow predicted to fall Tuesday airborne in some open areas surrounding the city. That's also the period in which an infusion of lake moisture is to begin, supplementing snowfall. Lake enhancement of snowfall could end up spanning 10-14 hours, extending into the opening hours of Wednesday morning even as non-lake-effect snow tapers to passing flurries at inland locations. It's an important reason this storm's heaviest snow totals are predicted to occur in lakeside counties of Illinois, Wisconsin and Indiana.
Explosive intensification of the storm is predicted by computer models later Tuesday as a secondary center forms off the mid-Atlantic Coast. Storms intensify when air rushes aloft at increasing speed. Ground-level winds strengthen as part of this intensification process. The rate at which air ascends increases, encouraging air to rush in from the storm's periphery at faster speeds to replace the upwelling of air at the heart of the storm.
The impact of the current storm's intensification across the Chicago area could become most noteworthy Tuesday night when winds approach their peak, gusting as high as 30 to 40 mph, particularly in areas surrounding the city. Winds of that strength should easily lift snow and hurl it through the air, producing near-blizzard or blizzard conditions. A blizzard is defined by the National Weather Service as three or more hours with winds gusting to or above 35 mph, and during which blowing snow reduces visibilities to a quarter mile or less. The density of structures such as homes and buildings in the city and close-in suburbs often generates enough drag on the moving air to subdue velocities there. But this doesn't happen in open areas surrounding the city, and these areas appear particularly vulnerable to potentially significant blowing and drifting snow Tuesday night.
Latest storm producing 1,300-mile corridor of snow; "Bosnywash" corridor being hit hard again
As unbelievable as it may seem, the Nation's Capital--where a snowfall of 1 to 3" can cause serious travel problems--is under the meteorological gun once again. Just three days from one of the region's worst blizzards in history, forecasters are predicting 10 to 20 inches of new snow may fall as winds strengthen later Tuesday. This promises a rash of new travel problems.
As low pressure moved out to sea Saturday, the mid-Atlantic states of Virginia, Delaware, Maryland, New Jersey and Pennsylvania were digging out of record snowfalls. Totals in the Washington,D.C. area ranged from a low of 17.9 inches at Ronald Reagan National Airport to 40 inches in the northern suburb of Colesville, MD. Dulles Airport reported a record 32.4 inches. Philadelphia measured 28.5 inches with just over two feet in downtown Baltimore. Atlantic City had 18 inches while New York City received just a trace of snow in Central Park. Even locations in western Virginia and Maryland and eastern Pennsylvania had 1 to 2 feet.
Chicago in path of next storm
A storm is forecast to move out of the central plains and merge with a strong upper air disturbance coming in from the northwest Monday. Snow is expected to spread into the Chicago metro area Monday night and increase in intensity Tuesday. At this stage it's still too early to determine the exact track the center of the storm will take, but if preliminary guidance proves correct, northeast Illinois as well as southeastern Wisconsin and northwest Indiana are in for significant snow accumulations. Strong easterly winds would causing considerable blowing and drifting snow making travel extremely dangerous.
The Mid-Atlantic continues in the grip of a crippling snowstorm as Saturday dawns. Snow is predicted to continue falling heavily into early Saturday afternoon amid howling northeast winds from Washington D.C. north to Baltimore, Philadelphia and Atlantic City. Final tallies are likely to exceed 20"--and may well top 30" in mountainous areas of Virginia, Maryland and southern Pennsylvania to the west of the Nation's Capital--more than in the pre-Christmas storm which clobbered the area.
The storm, which on Friday generated snow over a 1,000-mile swath extending from Missouri to the Maryland and New Jersey coasts, threatens to generate record-breaking snowfalls which may challenge some of the region's long-standing winter benchmarks.
More than 10" of snow had fallen in the Nation's Capital late Friday evening, and heavy snow continued falling nearly horizontally there in roaring 32 mph winds--slashing visibilities to near white-out levels. Dulles International Airport, situated outside Washington in northern Virginia, reported 1/16 of a mile visibility in heavy snow late Friday evening while visibilities at Reagan-Washington National Airport were down to a quarter mile. Frostburg in the Maryland mountains reported 15" of snow on the ground late Friday evening with thunder snow in progress, while 17.5" had fallen at Headsville, W.V., in the northeast corner of the state near the Maryland border.
Rapid intensification of the storm is predicted to generate 50-plus mph wind gusts and full blizzard conditions on the coast and in areas close-by including Atlantic City Saturday before the storm finally moves out to sea late in the day.
Storm snowfalls may challenge all time Washington & Baltimore benchmarks for the most snow
In Chicago, the benchmark winter storm was the Blizzard of '67 which crippled the city with a 23" accumulation delivered on roaring 50 mph gusts. But in Washington, the snow-producer of record is the Knickerbocker Storm of Jan. 27-28, 1922. That storm bears the name of the theater which suffered a deadly roof collapse when 28" of snow fell. The collapse killed 98 and injured 133.
Forecasters warned late Friday that the current system could produce accumulations in sections of the Washington area approaching such levels. Predicted totals of more than 20" from this storm in Baltimore could end up challenging the 28.3" record tally recorded there in the President's Day Storm of Feb. 15-18, 2003.
Modest snow Chicago area snow totals Friday
Snowfall Friday in Chicago was far less impressive, reaching an inch at a few mainly south suburban locations in the afternoon. Lansing topped the accumulation list with 1.4" of snow while 1.2" fell at Willowbrook and 1.1" came down at Richton Park. In the city, an inch fell at Midway Airport, but amounts tapered to just 0.2" at O'Hare. West suburban Oak Brook and Downers Grove saw just 0.5".
Sporadic lake-effect flurries are to ride gusty north to northeast winds into sections of the metro area Saturday, but any accumulations are expected to be modest.
Monday night/Tuesday system bears some resemblance to Jan. 7-8's snowstorm here
A significant Chicago snowfall remains a risk Monday night and Tuesday. Much can change in two days--but computer models late Friday continued to indicate a southeast-bound speed max in the jet stream is to sweep from the Dakotas later this weekend into central Illinois Tuesday--potentially placing Chicago in an area of strong atmospheric "lift" Monday night into Tuesday. That's a set-up notorious for snow production.
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.
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.
It's been nearly a month since the Chicago area has been blanketed by a fresh layer of snow as heavy as Tuesday's. The 1.7 inches which fell at O'Hare was the heaviest since an early January snowstorm buried the metro area under 7.4 inches of snow--the season's heaviest to date. Though snow accumulated from one corner of the Chicago area to another, its was the west and north suburbs which registered the heaviest totals. Accumulations of 2.5 inches hit Arlington Heights and St. Charles while Oak Brook and Lake Bluff registered 2.1 inches. The snow fell in a quiet wind environment and with temperatures which hovered near or just above freezing at many locations. This spared motorists on the area's major thoroughfares serious travels problems since road chemicals were able to work at maximum efficiency. Seasonal snow tallies surged to 31.9 inches Tuesday---well above the average of 22.4 inches to date--but just over a foot (12.1 inches) behind the same period a year ago.
Some sunshine breaks from the clouds Wednesday--and a southerly wind Thursday is likely to push temperatures above freezing for the first time in 11 days. But, the break in snowfall may be temporary. At least two systems capable of new snowfall loom in the coming week and are being monitored. The first is due Friday afternoon and evening and may, with the arrival of lake effect snows late Friday night and Saturday, extend into the first half of the weekend. Early computer estimates suggest significant accumulations are a good bet. Models run by the U.S. Navy and Environmental Canada put possible snowfall at 3 to 5 inches. Moderately colder air follows the windy disturbance into the area Saturday night and Sunday.
A possibly more potent system sweeps southeastward from Canada on Monday into Tuesday. Even colder arctic air may follow.
A winter like none recently in the Nation's Capital; District hit by new snow and another due late week
Washington, D.C., has already received more than 2 feet of snow this winter and another snowstorm is possible there this weekend. In stark contrast, at this point last winter, snowfall there totaled only 1.9 inches.
Snow--modest by February standards---greets poll-bound area residents Tuesday. It's the first to fall in February and marks the 20th day this season measurable snowfall has occurred . It comes only days after the close of a January which tallied just 9.1 inches of snow, more than 80 percent of which (7.4 inches) which fell in a single early month storm on Jan. 7-8. The month's snow tally was 11.3 inches below the most recent thirty year average and more than a foot (12.4 inches) below January a year ago.
Tuesday's slushy Election Day accumulations are likely to range from 1 to a little over 2 inches--most of it accumulating on untreated outdoor surfaces, such a side streets, sidewalks and driveways. Absent Tuesday will be significant wind and bitterly cold arctic air, regular visitors in early February. Only 14 years ago in 1996, the city shivered through a bitter three-day cold spell during which a majority of hourly temperatures remained below zero setting new records--not only for the coldest Feb. 2 and 3 overnight lows on the books since 1871, but for the coldest daytime high temperatures as well.
Coming days will be nowhere near as cold Daytime highs reach the 30s Tuesday and Wednesday and may make a move on 40-degrees away from Lake Michigan Thursday. These are temperature levels which assure road chemicals will work at maximum efficiency.
The sections of the metro area which receive 2 inch tallies Tuesday will have received nearly half the total amount recorded here ALL of February 2009. The month logged measurable snowfall on only four days.
Snows end as sunshine emerges Wednesday. But a second system approaches Thursday bringing clouds back into the area even as southeast winds tap milder air and push readings in the sections of the Chicago area away from Lake Michigan to near 40-degrees. However, the warming will be short-lived. Winds between a strong Canadian high pressure to the north and a developing storm to the south will increase Thursday and Friday. The gusty flow it is expected to tap the reservoir of arctic air covering much of Canada and the far northern tier of the U.S., tugging the frigid air southward into the nation's Heartland over the weekend and into early next week.
Miami area hit with Monday downpours; totals top 8 inches in spots
As the clean-up continued Monday in the wake of gargantuan weekend snows from New Mexico to Virginia and the Carolinas, thunderstorms drenched south Florida Monday, hitting an area from Ft. Lauderdale and Hollywood to Miami and Homestead especially hard. Flood warnings were hoisted after 8.13 inches drenched Cooper City, 7.61 inches Pembroke Pines and 7.38 inches at Ft. Lauderdale. The rains flooded area thoroughfares.
Winter 2009-10 opened with a snowy flourish with more than 28 inches falling in December and early January, but since then, only meager snow amounts have been recorded as the area's snow cover has dwindled to an inch or less.
Despite the recent lack of snowfall here, major snowstorms have buried the South and current national snow cover stands at 70 percent, the highest value recorded since observations began back in September 2003.
While no major snowstorms appear in the offing for Chicago, two systems have the potential to deliver accumulating snow. The first on Monday night and Tuesday should be a minor event bringing an inch or two with heavier totals expected north and west of the city. The second one, slated to arrive Friday night, could start out as rain but change to accumulating snow as colder air returns on Saturday.
Extreme cold lacking
With two-thirds of meteorological winter behind us, the city has officially recorded only one day with below zero readings: a low of minus one on Jan. 3. By this time last winter the city had recorded nine subzero days, including a low of 18 below zero on Jan. 16.
Cold weather continues to grip the Chicago area this weekend, but aside from a dusting of lake-effect snow in the city and northern suburbs Friday night and early Saturday, dry weather was the rule. In sharp contrast, the South is reeling from another major winter storm that left a three-day, 1500-mile-long legacy of snow and ice from Kansas and Oklahoma all the way to the Atlantic coastal areas of Virginia and the Carolinas. More than a foot of snow fell in many areas including 13 inches at Lynchburg and Forest, both in Virginia, and 13 inches at Mills River, N.C. South of the snow, a heavy glaze caused extensive damage to trees and power lines and created an icy havoc on roads. This is the second major storm of the winter to blast these areas, the first occurring in the days leading up to Christmas.
Snowy primary day shaping up
The next weather system is likely to spread its wintry precipitation farther north, bringing some snow to the Chicago area Monday evening and continuing into Tuesday, the day of the Illinois primary. While a major snowfall does not appear to be in the offing, it does appear that at least a couple of inches of snow could accumulate here by Tuesday afternoon.
January moves into its final two days this weekend, closing as it opened--COLD! The bitterly cold readings are easing slowly with time. Daytime high temperatures warmed from 13 to 21 degrees Thursday to Friday, and even higher readings are on tap Saturday and Sunday. But while the mid to upper 20s predicted both days continue the recent temperature upswing, they will fall nearly 20 degrees shy of last weekend's unseasonable mid-40s.
Flurries continue fluttering earthward as Saturday gets underway. A modest lake-effect snow event is in place--but the depth of the day's cloud layer is shallow compared to those which have produced more prolific and heavier snows in the past. Barring the unexpected, accumulations appear likely to remain limited, both in depth and areal coverage. Winds are to become even less supportive of lake snow development as the day proceeds, allowing precipitation to taper to sporadic flurries this afternoon and evening.
Longer days, strengthening sunlight hits milder temperatures ahead
It takes a while to transition from one season's temperature regime to the next. But the astronomical groundwork for the move to spring is falling into place. Days are lengthening and the strength of sunlight is on the rise. Chicagoans can look forward to an additional hour and 15 minutes of daylight in the next 30 days--and to two hours and 45 additional minutes of sun two months from today. Though it may seem an eternity to the winter weary here, Chicago weather records reveal the average final 32-degree temperature occurs on or about April 19th at Midway Airport and April 26 at O'Hare Airport. And the majority of daytime highs reach or exceed 70 degrees in Chicago 50 percent or more of the time beyond May 23.
Winter woes from Mid-Atlantic westward into the Midwest
While chilly here, Chicago's weather problems pale in comparison to those of recent days along a 2,000-mile swath extending from New Mexico and Oklahoma east to the Carolinas and Virginia. There, heavy wind-driven snow accumulated to a depth of as much as 14" in spots. Snowfall Friday piled up quickly in North Carolina, reaching 9" at Asheville by nightfall. Storm tallies since Thursday include 14" at Gruver, Texas; 10" Enid, Okla.; 11" Ingalls, Kan., and 8" Henderson, Tenn.
Snow could fly Monday night and Election Day (Tuesday)
An eastbound disturbance off the Pacific may be the next to deliver snow to the Chicago area. The period in question is Monday night into Primary Day (Tuesday). Temperature changes at high altitudes offer forecasters clues on the potential extent/intensity of snowfall a weather system may produce. Projections from computer models in the Monday through Tuesday time frame is hinting at fairly impressive warming at high levels of the atmosphere (around 40,000 feet). It's a development which suggests air within the system is likely to be rising vigorously enough to support sticking snow. The system will be monitored in coming days as it proceeds toward the Midwest.
