2007 U.S. Weather Summary: Over 900 High Temperature Records

The year featured crop-killing freezes in California in January and the Great Plains and Southeast in April, severe drought in the Southeast and Southwest, heavy rains in the Plains States through summer, and a hot summer for most of the Nation. Timely rains kept most of the Corn Belt out of drought during the summer growing season.

Winter (December 2006 February 2007): December's abnormal warmth carried over into early January 2007. January 6 represented the peak of the unseasonable heat in the East, when thermometers reached more than 70 degrees Fahrenheit as far north as upstate New York.

On January 11, the weather pattern over North America began a major change, and frigid Canadian air plunged southward, first across the western and central States and eventually the East Coast. Several nights of subfreezing temperatures severely damaged citrus and other crops in California, as temperatures dipped into the teens. In the San Joaquin Valley, thermometers dropped to 23 degrees Fahrenheit at Fresno on January 13 and, farther south, Lancaster broke daily-record lows on 6 consecutive days from January 14-19, reaching 3 degrees on the January 14, its lowest January temperature on record. As the cold air edged eastward, warm air overrunning set the stage for widespread freezing rain across the Plains and Mississippi Valley. The ice storm that struck the Oklahoma and Missouri area left some 400,000 customers without power on January 12.

The abnormal cold persisted through most of February, resulting in the coldest February Nationwide since 1994. Chicago saw subzero temperatures on February 3, 4, 5, 6, and 7, with a reading of 10 degrees Fahrenheit on February 5. On February 4, for the first time in 11 years, daily highs remained below 0 degrees Fahrenheit in Madison and Milwaukee, Wisconsin. The cold air spreading out over the warmer waters of the Great Lakes triggered huge snowfalls in upstate New York during February 3-8, Parish measuring a total of 88 inches. In the West, Denver residents saw snow on the ground for the 49th consecutive day on February 7, the longest such streak since 1984.

A major Valentine's Day storm spread large snow totals across the Midwest and Northeast in mid-February, with 17 inches blanketing Cleveland on February 12-14, and Burlington, Vermont setting an all-time record with 25.3 inches on the 14th. An enormous winter storm system later in the month tracked northeastward from Colorado, bringing heavy snow to the upper Midwest on February 23-26, including a record 21 inches at La Crosse, Wisconsin.

Spring (March May): Abnormal mild weather returned in March, and the month ended up with coast-to-coast anomalous warmth. Over 900 high temperature records were established, mostly during the week of March 11-18, and the contiguous U.S. ranked as the second mildest March in 113 years. Monthly temperatures averaged 10 degrees above normal in parts of the Plains.

A number of intense low-pressure systems led to snow, flooding, or severe weather this month. March 1 rainfall, for example, set a record for the date at 2.38 inches in Asheville, North Carolina. Grand Forks, North Dakota notched a daily record on March 1, with 9.0 inches of snow. Flooding was widespread early in the month, with streams over their banks from Iowa to New York. A severe weather outbreak on March 1 resulted in 31 reports of tornadoes in the Midwest and Southeast. Flash flooding struck Texas at mid-month. A Nor'easter on March 16-17 dropped up to 23 inches of snow in Columbia County in upState New York. A major winter storm on March 28-29 led to heavy snows in the northern Rockies and severe weather in the Plains. The resulting blizzard left 6-foot snowdrifts in Wyoming, and there were over 60 reports of tornadoes in the Plains. Abilene, Texas, measured 4.28 inches of rain for the month, its third wettest March on record.

A massive high pressure system plunging southward from Canada brought record cold during April 7-9 for much of the eastern half of the country. St. Joseph, Missouri, registered record low temperatures on April 7, 8, and 9, the latter day seeing readings plummet to 20 degrees Fahrenheit. In Arkansas, North Little Rock tied its April record low with 30 degrees Fahrenheit on the 7th and 8th. In Tennessee, Nashville's 24 degree reading on the 8th made this its coldest Easter Sunday since 1940. On the Plains, the 15-degree reading on the 8th in Concordia, Kansas was the city's latest spring reading of 15 degrees or less. The previous warmth and subsequent early growth of vegetation made this freeze especially damaging to field and tree crops, and damage was widespread from the Plains to the Southeast.

A major Nor'easter hammered the East Coast on April 15, while heavy rains lashed the Deep South to New England, and unseasonable snows blanketed northern New England and the higher elevations of upstate New York. New York City's 7.57 inches of rain on the 15th was its greatest daily rainfall since 1882.

April also featured outbreaks of severe weather. In the lower Mississippi Valley, there were 594 reports of large hail and damaging winds on the 3rd, including 14 tornadoes. Another outbreak on April 24 saw 197 reports of severe weather from Texas to Missouri.

Drought became a major concern in the Southeast this spring and intensified during the summer, eventually reaching a scale of historic proportions. Alabama, Tennessee, and Mississippi recorded the driest February-April in 113 years of record keeping. Georgia sustained its second driest such period. Florida notched its second driest April. Farther west, southern California measured its driest November-April on record.

In contrast, severe weather accompanied by heavy rains struck the southern and central Plains during the spring. During May 3-7, severe weather, heavy rains, and flooding affected an area extending from Texas to Minnesota. An EF5 tornado destroyed the town of Greensburg in southwest Kansas on May 4. Extensive flooding continued into May 10, rivers spilling over their banks in Texas, Oklahoma, Kansas, Missouri, Nebraska, Iowa, South Dakota, North Dakota, and Arkansas. The 8.73 inches of rain that inundated Columbia, South Dakota on May 5-6 established a new State record for 24-hour rainfall. On May 23, torrential rains of up to 8 inches hit parts of Kansas and the Texas Panhandle.

Summer (June August): Los Angeles ended up with its driest "rainy season," defined as July 1 to June 30, since records began in 1877. The weather station downtown mustered a scant 3.21 inches of rain for the 12 month period. Ample mountain snows in the preceding winter mitigated the impact of the drought on water supplies, as most reservoirs maintained enough water to avoid major water supply problems.

In the Southeast, however, the dry weather and the onset of the summer heat had a marked impact on reservoirs as well as crops. By early June, officials declared drought emergencies in 19 counties in northern and central Alabama. Tropical Storm Barry brought relief to Florida and Georgia during the first days of June, but drought persisted and even grew worse over interior areas. Four States measured their driest January-August in a century: Alabama, Tennessee, North Carolina, and Florida. Georgia and Mississippi earned the number two ranking. By early October, the U.S. Drought Monitor's highest level of drought, D4, extended from Alabama and western and northern Georgia into Tennessee, eastern Kentucky, and the Carolinas.

Farther west, flooding problems continued for the southern and central Plains into summer, Texas recording its wettest January-August on record. The wetness peaked in June, when low pressure aloft sat over the southern Plains for some 2 weeks, leading to episodes of torrential rains. On June 29, flood warnings stretched from southern Texas all the way to central Missouri. Flooding continued into early July. Dallas-Ft. Worth measured its wettest June-July since 1973, with 16.52 inches of rain.

Heat was one of the biggest stories during the meteorological summer of 2007 (June-August), which was the sixth-hottest summer on record, but there were exceptions. Much of Texas stayed below normal for the summer thanks in part to the moist ground. Temperatures soared in July across the West and the northern Plains. Las Vegas, Nevada, endured 116 degrees on July 5. The reading of 105 degrees at Reno on that day tied their all-time high temperature. Portland, Oregon, reached 102 degrees on the 10th. In Boise, Idaho, temperatures hit 100 degrees F every day from July 12 through 17. The monthly average temperature of 83.1 degrees not only set a record for July, but set a record for the hottest month ever.

Low rainfall and high temperatures led to expansion of drought into much of the interior West and heightened wildfire danger. Boise, Idaho, measured a mere 0.02 inches of rain for the entire month of July, while temperatures averaged 8 degrees above normal. By late July, large wildfires were scorching forests across northern Nevada, eastern Oregon, eastern Washington, Idaho, western Montana, and Utah. The largest fire in the State's history burned 363,000 acres in south-central Utah.

Heat was even more widespread in August, the second warmest August in at least 113 years Nationwide. An historic heat wave gripped the Southeast from around the 6th to the 17th, when triple digit heat was commonplace. Montgomery, Alabama, for example, notched a 100-degree reading every day from August 6 to 17, the 12 consecutive days of century temperatures easily breaking the previous record of 7. Although somewhat lower temperatures arrived later in the month, eight States in the region (West Virginia, Kentucky, Tennessee, North Carolina, South Carolina, Alabama, Georgia, and Florida) measured their warmest August on record. In the West, heat persisted as well, with Utah recording its hottest August.

Tropical weather systems played a role in the southern Plains wetness. Tropical Storm Erin came ashore in Texas on August 16 and renewed flooding in Texas. San Antonio recorded 8.81 inches of rain on the 16th. Over the next few days, the remnants of Erin dropped up to 10 inches of rain on eastern Oklahoma, causing flooding there as well.

Across the Midwest, Erin's moisture contributed to torrential rains over Iowa, southern Minnesota, and southern Wisconsin. During August 18-19, up to 15.10 inches of rain fell in 24 hours in southern Minnesota, setting a State record. Heavy rains a few days later led to significant flooding in the lower Great Lakes region. Several cities from Minnesota to Illinois ended up with the wettest month on record, including Madison, Wisconsin, with an August tally of 15.18 inches.

The upper Midwest, especially Minnesota, had been experiencing drought before August's heavy rains, due to below-normal rainfall from May to July. The deluge ended drought in southern Minnesota, but local drought persisted farther north to year's end.

For the Corn Belt as a whole this summer, drought on occasion crept northward from the south, affecting areas near the Ohio River, or touched the northern boundaries, but rains came at the right time for most farmers, and June-August cumulative rainfall was near to above normal for most of the region, with overall temperatures averaging just slightly above normal.

Only one hurricane made landfall in the contiguous U.S. this year. Humberto exploded in intensity on September 13 in the western Gulf of Mexico, ascending from depression strength to a Category 1 hurricane in less than 24 hours. The storm brought up to 14 inches of rain to east-coastal Texas. The storm did bring welcomed rains to drought-stricken parts of the Southeast, including nearly 2 inches to Birmingham, Alabama.

Autumn (September- November): Drought worsened during early October in many parts of the East. But a storm system that brought widespread severe weather from the Gulf Coast to the Midwest delivered drought-breaking rains of up to 14 inches to northwest Florida on October 18-19.

Short-term dryness reached extreme levels by October from the mid-Atlantic into New England. In Washington, DC, October 18 was the 34th consecutive day without measurable rain, breaking a record going back over a century. Drought also affected parts of southern New England. Record heat during the first 10 days of the month across the northeast quadrant of the Nation added to the drought problems. A major frontal system that tapped tropical moisture from the Gulf and Caribbean soaked much of the region during October 22-27. Baltimore picked up 5.43 inches of rain, and Washington DC recorded 6.18 inches during October 24-27. In Tennessee, Nashville measured 4.05 inches on October 22-25. Although the rain was not enough to end the drought in the Southeast, it did reduce the area and intensity of the drought.

On the West Coast, a period of Santa Anna winds led to tragedy in southern California. Winds up to 100 mph during October 21-23 fanned wildfires across southern California. The flames burned more than 800 square miles and displaced at least 500,000 people.

Parts of Hawaii experienced drought for much of the year until torrential rains associated with a Kona storm struck the islands, dropping 7 to 10 inches of rain on much of Oahu during the week ending November 6. Up to 7 inches of rain fell in 12 hours on November 3-4.

At the same time, the remains of Hurricane Noel slashed the New England coast. On November 3, Barnstable in Massachusetts measured a peak gust of 89 mph. Two to 4 inches of rain drenched Cape Cod.

In the southern Plains, dry weather became a concern for farmers despite the widespread heavy rains earlier this year. September rainfall was below normal over large parts of Oklahoma and Texas, and rainfall was below normal over a large area in October from western Kansas to Texas, with November continuing the dry pattern except for the Texas upper coast and southwest. By the end of November, cumulative rainfall since September totaled less than 40 percent of normal from western Kansas into western and southern Texas, resulting in low topsoil moisture.

December: The last day of the year featured a steady parade of storms bringing rain, ice, snow, and wind to much of the Nation.

A major Pacific storm slammed into the Pacific Northwest during the first days of the month. Up to 10 inches of rain inundated coastal areas and, during the storm's peak on December 2-3, winds gusted to 100 mph along the Washington and Oregon coasts. Western parts of Oregon and Washington experienced their worst flooding in over 10 years.

Heavy rains and mountain snows also struck the Southwest during November 30-December 1, with 3.71 inches of precipitation at Flagstaff, Arizona, and 2 feet of snow in southwest Utah.

A major winter storm brought widespread ice and snow to the Midwest on December 1-3, but this was eclipsed by an even larger ice storm on December 9-10. Freezing rain iced up a large area from Oklahoma to Kansas and parts of Nebraska, Missouri, Illinois, and Indiana. Ice accumulations from 0.25 to more than 1.0 inch caused massive power outages across the central Plains and paralyzed travel. On December 11, some 618,000 customers had lost their power in Oklahoma, making this their worst ice storm on record. Over 200,000 customers in other States also lost power. A wave forming on the cold front associated with the ice brought heavy snows to New York and New England on December 13. Up to 12 inches of snow piled up in Massachusetts, snarling the Boston area commute.

Another large storm system spread snow and sleet from the Midwest to the Northeast on December 15-16. In the West, heavy rain and snow eased drought in California during December 18-20. Fresno's 1.64 inches of rain on the 18th made this its wettest day since January 2, 2006. Still another winter storm dropped widespread snow across the Plains on December 22-23, and a later storm dropped several inches of drought-easing moisture on the Southeast during December 28-30. December 30 was Atlanta's wettest day (1.30 inches) since September 13. The improved rains this month prevented Atlanta from recording its driest year, 1954 edging out 2007 for this distinction.