Tonight: Spotty to scattered thunderstorms are developing this afternoon and evening in Northern California with some storms making it into central and southern portions of Klamath and Lake Counties. With the threat for lightning, critical fire weather conditions are in place in these areas for the threat of lightning-caused fire starts. Westside valley locations and areas along the coast will stay dry. Showers and thunderstorms will be ongoing in parts of our region through the evening hours before that activity comes to an end overnight. Once the showers and thunderstorms exit the area tonight, no more activity is expected for the next several days. Clear skies will persist in Southern Oregon and Northern California tonight with mild to warm temperatures. Overnight lows will fall into the upper 50s to low 60s west of the Cascades with upper 40s to mid 50s east of the Cascades.

A RED FLAG WARNING has been issued for Siskiyou County until 7 PM tonight. During this time, numerous lightning strikes over dry fuels may start new wildfires. Gusty and erratic winds associated with thunderstorms may also help spread any existing wildfires. Use caution and be fire aware in this area.

Tomorrow: Friday is looking dry across the region, but temperatures will be heating up significantly. Skies will be sunny to mostly sunny with just morning marine layer clouds and fog impacting parts of the coast. Highs will be up around 100 degrees in our westside valleys with lower 90s expected in the Basin. The coast will be comfortable and cooler compared to inland areas with highs near 70 degrees.

Extended: This weekend is looking very hot with dangerous daytime high temperatures into the triple digits in our westside valleys with even temperatures above 100 degrees in some higher elevations and the eastside. Highs could push 113 degrees or higher in some of our westside valleys on Sunday. The Klamath Basin will likely see triple-digit heat Sunday into Monday. The heat will linger into at least the start of next week. Plan on some warm nights as well. High temperatures records could be in jeopardy with this heat wave through the weekend. This long-duration heat wave will increase the chances for heat-related illness. Be sure to take breaks from being outdoors in the heat and stay hydrated.

An EXCESSIVE HEAT WARNING has been issued for all of inland Southern Oregon and Northern California from 11 AM Saturday through 11 PM Tuesday. During this time, daytime highs will very hot with the westside seeing highs between 100 to 115 degrees and the eastside seeing highs between 95 to 105 degrees. Our nights will be much warmer too. These weather conditions will increase the chances for heat-related illness. Be sure to take breaks from the heat and stay hydrated.

Next week looks to stay very hot with dry weather continuing through at least Tuesday. The heat will increase fire danger though across the region. Be sure to practice good fire prevention outdoors. We'll need to watch next Wednesday and Thursday. Some forecast models are hinting at thunderstorm chances for parts of the region.

Stay updated on the StormWatch 12 forecast on-air and online.