Erratic jet stream brings extremes and warnings to U.S.
June 27, 2013
ARIZONA – Temperatures will be at full throttle later this week over the interior West, reaching dangerous levels, challenging records and elevating the wildfire threat. While many folks over the interior West are accustomed to and expect hot weather during the summer the developing pattern will take the heat to the extreme. In some cities record highs for any date throughout the year could be equaled or breached. The weather this week will favor an expanding area of sunshine and building heat over the West. As temperatures soar to record-challenging levels, dry fuel and the potential for spotty dry thunderstorms will push the wildfire threat to new areas and raise the risk in other locations. Once the pattern sets up, the heat wave will last through next week in many areas. Grassy and wooded areas that are green now may become dry fuel for fires as the atmosphere heats up. Cities that will experience record-challenging heat on a daily basis during the pattern into next week include Las Vegas, Phoenix, Salt Lake City, Denver, Boise, Idaho, Rawlins, Wyo., Medford, Ore., and Fresno, Calif
According to Western Weather Expert Ken Clark, “People driving through desert areas during the pattern should make sure their vehicle can make the journey and that they carry extra water in case their vehicle breaks down.” With time, the heat can expand to part of the California coast by way of a slight offshore flow. However, the worst of the heat will hold up just inland. The pattern will make the beaches a hot spot to avoid the heat. The system producing the heat and sunshine will allow widely separated, pop-up thunderstorms with time. Most of the storms will form and die over the mountains, but there will be a few exceptions. A few locations can receive a downpour. However, many of the storms will bring little or no rainfall. This phenomena, commonly called “dry lightning,” can spark new wildfires. Meanwhile, on the U.S. East Coast, as rainfall continues to pile up into early July, some locations could be hit with major travel disruptions, flooding damage and even a life-threatening weather situation. –Accuweather