Europe Braces for Extreme Cold Snap (credit: Met Office UK, Washington Post, Climate Reanalyzer)2/28/2018  DISCUSSION: Between February 26th and March 4th, Europe will experience an extremely cold snap with temperatures falling way below freezing. This could bring some of the most extreme temperatures since the cold snap back in 2013.
A negative phase of the North Atlantic Oscillation is an atmospheric pattern where the stratosphere above the North Pole warms, resulting in polar vortex over mid-latitude areas. This pattern is known to create cold temperatures and bring along stormy weather for the affected regions. These patterns are also known to bring strong snowstorms to the East Coast of America as well. The cold air that will flow into Europe allows air to evacuate the Arctic, making temperatures there warmer than normal. This pattern creates a high-pressure system, drawing air clockwise and bringing in cold air from Siberia. Average temperatures during this time in Europe average from 3 - 16 degrees Celsius, but temperatures are expected to be 10 degrees Celsius below normal. The highs in London are projected to stay around 0 - 4 degrees Celsius, with wind gusts making it feel a lot colder. While most of Europe is already under a yellow warning for snow, places in southeast England are under an Amber warning. A yellow warning just means to be aware that severe weather is coming and an amber warning means to be prepared for the increased likelihood of extreme weather. Furthermore, with this accumulating snow, transportation is expected to be affected during this cold snap. Europe isn’t the only place experiencing these cold temperatures either. Areas as far south as France are enduring below normal temperatures for this time of year. The increase in internal heating resulted in France’s natural gas levels spiking within the last few days to its highest level since 2008.Temperatures in France haven’t dropped this low since the cold snap back in 2005. On the other hand, places in the Arctic are experiencing record warmth. In Cape Morris Jesup, the northernmost point of mainland Greenland, temperatures have been above freezing between February 16th- February 25th. The warmth in this area over the Arctic have resulted from the same pattern that is bringing the brutally cold air into Europe. (Citied: Met Office UK, Washington Post, Climate Reanalyzer) To learn more about other winter weather stories from around the world, be sure to click here! © 2018 Weather Forecaster Allison Finch
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Forecast Discussion: Wet Winter Weather for Isles (Credit: National Weather Service Honolulu)2/18/2018  Image Courtesy: NOAA NESDIS DISCUSSION: Climatologically there are seemingly only two seasons in Hawaii, these being summer and winter. While there are over 10 climate zones experienced in Hawaii, it can be apparent that summer is often May through October with Winter from November to April. Much like the Eastern Pacific portion of the United States the winter is often the wet season for Hawaii, diminishing the coveted trade wind weather and bringing a slew of cold fronts and/or troughs of poor weather with increased precipitation, often posing major hazards to the area. President’s Day and its week are expected to see some of this wet and typical weather for mid- winter season. The island chain is under a rather slow trough located at the surface with an upper-level disturbance bringing in round after round of thunderstorms to the islands. These unstable conditions are bringing widespread lightning, thunderstorms, and flash flooding to the island especially in windward location of the islands. With some winds out of the south, the chain has been experiencing unsettled weather associated with this moisture plume bringing increased possibilities for water spouts, thunderstorms, and lightning. The National Weather Service Honolulu (NWS) has issued a flash flood watch for the entire state, as moderate to heavy rain falls. In addition, the NWS has issued a winter weather advisory for the Big Island summits (Mauna Loa and Mauna Kea) as snow is expected to fall with this system. Due to the precarious nature of this forecast, moisture will remain in the area as this unstable weather will be supported by a trough, and a developing upper level low. As the trough evolves into a closed low over the next day or so, heavy precipitation will persist, the atmosphere will become increasingly unstable and the NWS has indicated, “updraft strength becomes sufficiently strong to support the development of small hail and funnel clouds.” Diagram 2, current analysis for the Skew-T diagram has indicated K-index of 33 a moderate potential for convection, total totals at 53 indicating widely scattered severe storms, as verified by radar, however Lifted index only -4 indicating marginal instability. Overall there’s increased potential for convective action and flash flooding but no determination for extreme instability regarding the slow-moving trough. This wet pattern is expected to stick throughout the week, with at least some marginal chance for precipitation each day. For more forecast discussions or information about weather in your locale, visit the Global Weather and Climate Center! © 2018 Meteorologist Jessica Olsen  DISCUSSION: It is important for the National Weather Service to issue weather-related warnings to the public for their safety. A new type of snow warning called a “snow squall warning” can be issued, as of January 3rd, 2018, by the National Weather Service. A snow squall is a sudden, short period of heavy snowfall accompanied by strong winds and occasionally lightning. During this time, snow accumulation may be substantial.
Snowstorms and snow squalls are much different. A snowstorm can be predicted days in advance. They are typically larger in scale and affect more area than snow squalls. Also, the likelihood of an accumulation is always greater with snowstorms than with snow squalls. Although accumulation is less with a snow squall, the sudden reduced visibility from sudden heavy snowfall causes danger to travelers. Snow accumulation is typically around 1 to 2 inches of snow with visibility that can be less than one quarter of a mile and is expected to last less than an hour. According to the National Oceanic and Atmospheric Administration (NOAA), the new warning can be issued in the following NWS offices: Buffalo, NY; Detroit, MI; Cheyenne, WY; Pittsburg, PA; State College, PA; Binghamton, NY; and Burlington, VT. These warnings are first sent from the Advanced Weather Interactive Processing System (AWIPS) to the National Weather Service (NWS) as a code. For example, “SQWBUF” is the Buffalo, NY snow squall warning code. If the weather forecast office in Buffalo, NY was to receive that code, the NWS would then issue a snow squall warning to the public for that area. The NWS has given advice if a snow squall warning is issued in your area: 1. Consider avoiding or delaying travel until the snow squall passes your location. 2. If you must travel, use extra caution and allow for extra time. 3. Rapid changes in visibility and slick road conditions may lead to accidents. It is crucial that the public is notified as soon as possible. According to The Weather Channel, research indicates many highway pileups are attributed to snow squalls each winter season. For example, on March 20, 2017, there was a 30-car pileup on Interstate 81 in Schuylkill County, PA that killed one person. Similarly, there was a 50-car pileup on February 13, 2016, in Lebanon County, PA that killed three people. These are just a couple examples of some of the highway accidents associated with snow squalls. They create low visibility and slippery road conditions that cause tires to lose traction on the road. Most of the time, snow squalls create minor snow accumulations as opposed to greater totals dropped by snowstorms. NOAA states that they can now better predict short-term weather events with the new GOES-16 satellite as well as, recent improvements in Doppler-radar, and more accurate and detailed weather models. Some of the short-term weather events which can now be detected quickly include snow squalls, thunderstorms, and tornadoes. With this new technology, the NWS can alert the public in a timely manner and reduce snow squall related accidents. (Credit: NOAA, The Weather Channel) To learn more about other winter weather stories from around the world, be sure to click here! ©2018 Weather Forecaster Brittany Connelly |
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