2007 North America South and Eastern heatwave

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The 2007 North America South and Eastern heatwave was a continuation and eastward expansion of the 2007 Western North American heat wave which began in late June 2007, and is still ongoing in parts today. As expected the heat from that heatwave expanded eastward starting at the very end of July and lasting into the first weeks of August. The heatwave is still ongoing in parts of the southern/central plains, Mid-Mississippi River Valley, and into much of the southeastern and Mid-Atlantic states of the United States.

1 Environmental impacts
2 Deaths and health impacts
3 Meteorological setup
4 See also
5 References
6 External links

[edit] Environmental impacts

So far the North American South and Eastern Heatwave is responsible for oppressive heat and building drought across the central and southern midwest and into the southeast. Temperatures were soaring into the upper 90s and low 100s as far north as Kansas City, MO and Saint Louis, MO. Much of the south is experiencing highs topping out around the century mark as far east as Charleston, SC and New York City, NY. On top of the actual temperatures being high, the humidity levels were in the 50s to 60s percent levels, and dew points in the upper 60s to mid 70s creating Heat Index values of 105 or more in much of the affected areas. For that reason, nearly two dozen states either have Heat Advisories, or Excessive Heat Warnings or Watches, with the area of most watch or warning coverage in the Mississippi River Valley region from Illinois and Missouri down to Louisiana and the Southeast Atlantic Coast, as well as parts of the Mid-Atlantic.

13 new all time maximum high temperatures were set, along with several hundred new daily high maximum temperature records.^[1]

Besides for the temperatures, the nature of the heatwave and the accompanying high pressure system area causing intensifying drought conditions, especially in areas that are already experiencing exceptional drought conditions, such as northern Alabama where the drought was exceptional even before the heat wave. It is also initiating drought conditions into the Ohio and Mississippi River Valleys. Depending on exactly how long this heatwave lasts, it could have a major impact on the agricultural harvest as September and October approaches. The drought conditions will also most likely create conditions that are more favorable for wildfires and create water shortages in some communities that are already dealing with low water levels. The persistent drought and heat wave have further decreased soil moisture to below 98-99% of normal levels.^[2]

[edit] Deaths and health impacts

More than 50 deaths^[3] have been reported as well as cases of Heat exhaustion and Heat Stroke. Most occur in the very elderly and people who could not afford air conditioning due to high energy costs. Fortunately these are sporadic cases, and most healthy people are handling the heat due to advance warning, and better preparation procedures. Most likely to be affected by the excessive heat are those working consistently outdoors, performing strenuous work, such as construction work, or other jobs requiring excessive pushing, pulling. It has been advised that people working these kind of jobs seek shade when possible, take frequent breaks, wear light colored, loose fitting clothing, as well as to drink plenty of clear non-alcoholic beverages even if you do not feel thirsty. Wearing sunglasses, sunscreen, and a wide brimmed hat aren't a bad idea either, as the UV or Ultraviolet Index is expected to top at above normal levels due to the extra dry and hot weather.

[edit] Meteorological setup

The heat wave is being triggered by several factors. First is an unusually strong upper level ridge that has settled over the southern plains and southeast near the Ozarks. Another is the sharp troughing over the Pacific Coast and offshore of the Atlantic. This in turn creates an Omega block pattern over the US and causing weather to persist for a period of days if not weeks in some cases. In the coming weeks the ridge is expected to retrograde back towards the west which will allow some short term relief for the northeastern states and Mid-Atlantic, but the Mississippi River Valley and southeast are not expected to get so lucky and will most likely stay in the oppressive heat for at least several more days. Some more widespread relief may come by the end of the month, but confidence is very low this far out. August 2007 will likely be one of the 20 warmest Augusts for the United States since 1895.^[4]