Departure of normal temperatures (F) Since May 1.

An intense heat wave has gripped much of northwest India over the past couple of weeks.

While may is normally the warmest month of the year, in advance of the summer rain season, this month has been exceptionally warm in many areas.

The capital city of New Delhi has had high temperatures at or above 100 F (or about 38 C) every day but one this month. That may not seem like much, considering normal high temperatures peak at 105 F (40.6C) on May 16. Afternoon temperatures have averaged 4-6 degrees F above normal since May 10, with a peak high temperature of 111 F (44.1C) occurring on May 17.

What has made this heat wave more unbearable has been the nighttime low temperatures. Low temperatures since May 9 have been 80 F (26C) or greater each night, or several degrees above normal as well. The low temperature has been as warm as 87 F (30.7C). To put this in perspective, 87 F is about what the normal high temperature reaches in Philadelphia, PA in late July and early August, and that was the nighttime low!

Some relief from the heat will finally arrive this weekend and will last into early next week.

A weak trough of low pressure in the upper atmosphere will sink southward over the next few days. This may touch off a few showers and thunderstorms across Northwest India each day this weekend into early next week.

These showers and thunderstorms will bring some cooling to the region as high temperatures will top out around 100 F (38F). These temperatures would be 4-6 degrees F below normal and a welcomed relief from the heat.

However, it appears the relief will be short-lived as temperatures slowly rebound by the middle and end of the week, becoming near- to above-normal once again.