Weather Forecast: Hot, Then Not

Super Bowl Sunday will be sunny and warm in Pasadena, and Monday similar though cooler — but Tuesday’s high could drop by almost 20 degrees and rain could fall, forecasters said.

The National Weather Service said Tuesday will top out at 66 after today’s high reaches 87 and Monday hits 83.

A high-pressure system continues Sunday to drive up Southland temperatures and could result in the hottest kickoff in Super Bowl history Sunday when the L.A. Rams and Cincinnati Bengals hit the field at Inglewood’s SoFi Stadium.

Temperatures are expected to be in the mid- to upper-80s when the big game gets underway at 3:30 p.m. Sunday. According to the Southeast Regional Climate Center, the warmest Super Bowl kickoff occurred in 1973 — at Los Angeles Memorial Coliseum — when it was 84 degrees.

The combination of heat, wind and low humidity will also increase the fire danger. Forecasters said humidity levels could drop as low as 6%, combined with the Santa Ana breezes and heat ranging from 80 to 90 degrees.

The NWS noted that “picture-postcard perfect weather will be on display Sunday for anyone seeing the LA coast on their TVs.”

The heat is expected to break on Monday, when “significant cooling” is anticipated, according to the weather service. A “cold storm system” will move in on Tuesday.

There is a 20% chance of rain in Pasadena on Tuesday, the NWS said.

Here’s a detailed look at the NWS forecast:

Sunday: Sunny, with a high near 87. East northeast wind around 5 mph becoming south in the afternoon.

Sunday Night: Mostly clear, with a low around 56. North northwest wind around 5 mph becoming east after midnight.

Monday: Sunny, with a high near 83. East northeast wind 5 to 10 mph becoming south southwest in the afternoon.

Monday Night: Partly cloudy, with a low around 54. South wind around 5 mph becoming east southeast after midnight.

Tuesday: A 20 percent chance of rain. Partly sunny, with a high near 66.

Tuesday Night: Mostly clear, with a low around 43.

Wednesday: Sunny, with a high near 68.

Wednesday Night: Clear, with a low around 49.

Thursday: Sunny, with a high near 73.

Thursday Night: Mostly clear, with a low around 50.

Friday: Sunny, with a high near 75.

Friday Night: Mostly clear, with a low around 52.

Saturday: Sunny, with a high near 75.