National Weather Service United States Department of Commerce

Dangerous, Heat Wave Persists in the Eastern U.S.; Severe Weather Expected in the Central Plains and Mid-Atlantic

A prolonged, dangerous heat wave will persist through the Independence Day weekend across the Ohio Valley, Mid-South, and East Coast. Severe thunderstorms are expected to produce damaging wind gusts from the Upper Ohio Valley into the Mid Atlantic, and across the central Great Plains this afternoon and evening. Large hail and heavy rain is also possible across the Great Plains. Read More >


The following graphics depict the number of days that a given site has reached 90 degrees or more this year (on the x-axis) and the annual precipitation to date (on the y-axis). Also included are prior years, color coded by decade, and the 10th, 25th, 50th (i.e., median), 75th, and 90th percentiles for each variable. These graphics show us how hot and dry (or cool and wet) the current year is compared to the period of record and may be useful in drought monitoring.

Many of these sites are maintained by cooperative observers, a program which you can learn more about here. We are in the process of quality controlling past data, so some of these values are subject to change. To view the percentiles, hover over a location on the left after choosing the desired region of interest along the top of the page. Data courtesy of the Applied Climate Information System.