WEATHER OVER THE WEEKEND -- The strong storm system and accompanying cold front that produced severe weather across the Midwest last Thursday continued moving northeastward, producing heavy rains across New England on Friday. Some locations received more than 2 inches of rain. By Saturday morning the system had moved off the coast, but rain continued to linger across New England.
Following this storm system and cold front, a large high pressure system accompanied by a chilly air mass moved into the nation's midsection. This high moved eastward into the Great Lakes States by Saturday and toward the East Coast by Sunday. Essentially the entire country experienced an unseasonably chilly Veteran's Day on Saturday, as afternoon temperatures for all but a handful of locations in New England and south Texas were well below the long-term average highs for the date. Residents in the Rockies and the Intermountain West experienced the greatest departures, with afternoon highs 30 degrees below the averages. On Sunday afternoon, high temperatures once again were on the order of 30 degrees below average across the Rockies. Numerous daily record low temperatures were set on Saturday and Sunday mornings. At Spokane, WA, the record low temperature of 2 degrees below zero on Saturday morning was the lowest temperature for so early in the season.
On Saturday morning a storm system developed along the lee slopes of the southern Rockies over northeastern New Mexico. Snow was falling to the north of the low pressure center across Wyoming, Colorado, Nebraska and the western Dakotas, with rain and freezing rain to the south and east across Oklahoma and Kansas. This system moved eastward across the Southern Plains on Saturday, accompanied by a band of snow that fell across Nebraska and the Dakotas. By Sunday morning the storm system had begun curving toward the northeast as it reached southwest Iowa. As much as 15 inches of snow had fallen across Nebraska and South Dakota. Some locales in western Minnesota received as much as 6 inches of snow by Sunday morning. Sufficiently warm air was brought into the Twin Cities on southeasterly winds that the morning snow changed over to rain by afternoon.
A cold front trailed southward from this storm system. A sharp temperature contrast was evident along the cold front across Texas, as temperatures on Sunday afternoon were in the 40s across north Texas, but near 80 along the Gulf Coast. This temperature contrast along the cold front helped produce the thunderstorm activity along the Gulf Coast. During the late afternoon, severe thunderstorms moved eastward from the vicinity of San Antonio to the Gulf Coast near Houston. High winds were reported, with the loss of a roof from a house attributed to an unconfirmed tornado southeast of Austin. However, numerous funnel clouds were sighted. Large hail also fell.
WEATHER FOR STARTING THE NEW WEEK -- The following highlights of the national weather have been extracted from the surface weather map for late Sunday night.
The storm system that produced heavy snows across the Plains on Saturday and early Sunday continued to move northward across the Upper Midwest. The low pressure center was located over south central Minnesota as of Sunday night. An occluded front stretched southeastward from the low center to the Ohio Valley where it continued as a cold front that curved southwestward to reach the Rio Grande Valley of south Texas. Strong northwest winds continued across the northern Plains to the west of the storm system as a tight pressure gradient remained between a high pressure center over northwest North Dakota and the low.
Snow continued to fall in the vicinity of the low pressure center, with an areal coverage that extended from the western Great Lakes across the Upper Mississippi Valley to the eastern Dakotas. Some rain also was wrapped into the eastern flank of the storm over portions of Wisconsin. Farther south, widespread rain fell along the cold front from Illinois southward to the Gulf Coast. Some snow was also detected in the cold air across the Ozarks of southwestern Missouri into northeast Oklahoma. Strong to severe thunderstorms continued along the Texas Gulf coast into Sunday night. During the evening hours, Hobby Airport in Houston reported a peak wind gust of 74 mph in a severe thunderstorm. A tornado watch was in effect during the early evening hours as conditions appeared favorable for tornado development. Some funnel clouds were spotted along with some tornadoes indicated on Doppler radar. However, no tornadoes were confirmed.
The storm system is expected to move toward the east-northeast on Monday, reaching western Wisconsin by morning and northern Lake Michigan by evening. Winter storm warnings remained in effect for northeastern South Dakota, southeastern North Dakota and western Minnesota, while snow advisories covered portions of eastern North Dakota and northwest Minnesota and winter weather advisories were issued for central and northeastern Minnesota, plus extreme northwest Wisconsin. The occluded front and the northern portion of the cold front should move eastward across the southern Lakes and the Ohio Valley on Monday. As much as 0.5 inches of rain could fall by Monday evening along the front in an area from the western Gulf Coast northward along the Mississippi Valley into lower Michigan. The southern portion of the cold front should push out over the Gulf of Mexico. As the front moves offshore, the risk of severe thunderstorms should diminish along the Texas Gulf Coast.
A cold front trailing from a storm system moving across the Gulf of Alaska was approaching the Pacific Northwest on Sunday night. Some rain was falling across Washington State's Olympic Peninsula in advance of this cold front. By the time the cold front reaches the Pacific coast on Monday, a low pressure center is expected to have developed along the front near the mouth of the Columbia River. Widespread precipitation is expected to spread along the coast, from Washington State to northern California. Coastal communities could receive as much as 0.5 inches of rain by Monday evening. Inland, the precipitation should fall as snow across the mountains of northern California. Two to five inches are expected in the foothills above 2500 feet and as much as a foot of new snow in the Sierras by Monday night. As a result, a winter storm watch was in effect for northern California and northwest Nevada.
The cold air remained across much of the western half of the nation. High pressure extended southward from the northern Rockies across the Plains and the Intermountain West. The cold air mass accompanied by weak winds and relatively cloud-free skies is expected to cause considerable overnight cooling. Freeze warnings were posted for a large section of the Hill Country of central Texas, as well as portions of southern Nevada near Las Vegas and southern California near Santa Barbara and San Luis Obispo. Frost advisories were also posted for California's Sacramento and San Joaquin Valleys.
UPPER AIR -- The 500 and 300 mb charts for 00Z Monday revealed a large pool of cold air that extended upward through the troposphere over the center of the continent. This cold air produced a large height trough with a cyclonic (counterclockwise) circulation on these two constant pressure surfaces in the mid and upper troposphere. However, this storm system had a slight tilt toward cold air. In other words, the surface low pressure center was located in south central Minnesota, at 500 mb the center of circulation appeared to be displaced slightly to the west to a point over eastern South Dakota, and on the 300 mb surface the circulation center was over central South Dakota. The strongest winds on the 300 mb surface formed the upper tropospheric jet stream around the southern periphery of the trough. Wind speeds exceeded 110 knots over Texas.
TEMPERATURE EXTREMES ACROSS THE LOWER 48 -- On Sunday, the lowest temperature reported in the continental U.S. was 25 degrees below zero at Jeffrey City, WY, while Sunday's highest temperature was 89 degrees at Harlingen and McAllen, TX.
ALASKAN WEATHER -- A powerful storm over the south central Bering Sea produced strong winds across western Alaska on Sunday afternoon. The low pressure system with a central pressure of approximately 952 mb was accompanied by an occluded front that curved eastward and then southeastward across the Bering Sea and the eastern Aleutians into the North Pacific. The tight pressure gradients surrounding the storm system produced southeast winds that reached 68 mph at Cold Bay, 62 mph at Dutch Harbor and 50 mph at St. Paul earlier on Sunday. Rain was also falling during the midday at Cold Bay and St. Paul. A weak storm system moving to the northeast across the eastern Gulf of Alaska spread clouds and precipitation across the Panhandle. The low pressure center was located just west of Sitka with an occluded front that stretched southward along the west coast of the Panhandle and British Columbia. As of Sunday morning, the 24 hour precipitation totals included Ketchikan with 2.27 inches, Yakutat with 2.18 inches and downtown Juneau with 1.36 inches. A small cell of high pressure extended from the central Yukon Territory westward across east central Alaska. As a result, some breaks in the overcast were found across the interior. An east-west oriented front that ran along the Brooks Range separated cold air over the North Slope from relatively warm air across interior Alaska. Snow and blowing snow was found along the North Slope and at Bettles and Tanana.
The lowest overnight temperature in Alaska as of Sunday was 11 degrees below zero at Arctic Village, and the midafternoon highest statewide temperature was 48 degrees at Dutch Harbor.
HAWAIIAN WEATHER -- Cloudy skies were found across the 50th State on Sunday. Low clouds were approaching from the east as an easterly wave, or disturbance in the easterly wind flow was moving to the west toward the islands. Some showers were found along the windward and mountain areas of all the islands. Strong easterly winds had speeds reaching 20 mph. These winds should weaken and become more southeasterly later in the week. Ocean waves generated by a distant storm near the Kuril Islands in the western North Pacific were expected along the northwest shores on Sunday evening. Because of strong trade winds, small craft advisories were posted on Sunday evening for all state waters.
REPORTS FROM THE FIELD -- Roger L. Skillman, a DataStreme teacher in Cashiers, NC reported on the 5.2 inches of rain that fell within 29 hours on last Wednesday and Thursday. The rain accompanied a frontal passage that also contained winds that blew down tree limbs and caused some scattered power outages. He said that this deluge fell after weeks of little or now rain and that their "temperate rain forest" remains about 15 to 20 inches below normal. Wells are dry, rivers are low, and plants and animals are stressed.
Eleanor Vallier-Talbot, LIT Leader from Charleston, SC and Savannah, GA forwarded an informative web site that explains the history involved with the institution of Daylight Saving Time not only in the United States but in other countries. This site is at http://deil.lang.uiuc.edu/web.pages/holidays/DST.html. This site has the potential for use in the classroom since it also has links to other items of interest, including the history of calendars and time.
WINTER AWARENESS --Indiana, Kentucky, Maine, Maryland, Ohio, New Hampshire, North Dakota, Virginia, Washington, DC and West Virginia are observing Winter Awareness Week during the upcoming week (12-18 November). In addition, Kansas Winter Weather Awareness Day on Tuesday, 14 November, while Missouri will have a similar event planned for Wednesday, Texas has its Winter Weather Awareness Day on Thursday and Tennessee has Winter Weather Awareness Days from Tuesday through Thursday (14-16 November). Residents of the states should take time to review the winter weather safety rules that have been prepared by their local National Weather Service Offices.
HAZARDOUS HIGHS -- We usually associate low air pressure with stormy weather and high pressure with "fair weather", a somewhat subjective term used to describe pleasant weather conditions, with no precipitation and few clouds. But can high pressure deliver "un-fair" weather? For a description of the types of hazardous weather associated with high pressure systems, please check Monday's optional Supplemental Information.
From the files of the Aviation Weather Center, Kansas City, MO and Intellicast