![]() Courtesy of NCEP WPC. In the top two maps, we can see how temperatures in Colorado and the general Northern Midwest are cooler than those of most of the country. The 500-mb map shows the upper level trough that enhanced lift in the state, allowing for the sustained precipitation throughout the past weekend. The precipitation map shows some 24 hour totals from Sunday for the US. Eastern Colorado received more rainfall than western Colorado. DISCUSSION: Just six days into the start of fall, Colorado is really feeling the change of the seasons. This past Thursday, Denver reached a record high of 92 degrees as one final summer hurrah. In contrast, Denver experienced highs in the low to mid 50s Saturday and Sunday, and felt some highs in the low 60s yesterday and today – a 30 to 40 degree difference in high temperatures! Along with this stark temperature change, the state of Colorado finally received some much needed precipitation, with rain falling across the state throughout the weekend. Another sign of the sudden change in seasons is the presence of snow. Elevations above 9000 feet received enough snow fall to grant the closure of the roadway to Mount Evans, and ski resorts are already preparing for the season as well.
Why the sudden change? A slow-moving cold front and upper level trough moved into the region Friday. It brought along a cold air mass that cooled Denver with temperatures that are typical of late October/early November. With plenty of moisture, and lift from the cold front, a jet streak, and the mountains, conditions were also perfect for sustained rainfall throughout the weekend. As the cold front continues to move east, conditions are expected to dry out and warm up in time for this coming weekend, with sunny skies and temperatures returning to the 70s. To learn about other high-impact weather events across North America, click here! ©2017 Katie McCracken
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Irma takes aim at Florida (Credit: NOAA/SSD via National Hurricane Center and NWS Key West)9/9/2017 DISCUSSION: As Hurricane Irma continues its final stretch to Florida, people are evacuating in a mass exodus from the storm. As Irma continues to crawl, it’s forecasted path continues to change as the main target has shifted west from the Miami-Palm Beach area towards Naples and the west side of the state. Many more cities including Tampa, Orlando and Daytona Beach are preparing for the storm. As time ticks closer and closer to the arrival, the escape routes have become much more limited and crowded as airports have closed or will close. In addition to the roads being crowded, many stores shelves are empty as those unable to leave grabbed the remaining supplies especially drinking water and wood to board up the doors and windows to help prevent massive damages from Irma. Irma has already impacted much of the evacuation, as Ft. Lauderdale-Hollywood and Miami airports officially closed Friday evening at approximately 9 pm. In addition, Tampa International announced they would be closing at 8 pm on Saturday due to the storm, while Orlando International announced their closure to be occurring at 5 pm on Saturday. Airports were not the only locations to announce their closures in Central Florida. Walt Disney World officially announced all the parks and attractions would be closed on Sunday and Monday, meanwhile, Universal Orlando announced they would also close early on Saturday and remain closed through Sunday and Monday. On Friday night, the National Weather Service expanded a Hurricane Warning across Florida with the northern boundary being drawn from Manatee County to Indian River County and as far south as the waters surrounding the Florida Keys. The NWS has also issued Hurricane Watches for much of the rest of the Florida peninsula including Tallahassee. In addition, the NWS office in Key West issued this tweet: To learn more about other high-impact weather events occurring across North America, be sure to click here!
©2017 Meteorologist JP Kalb DISCUSSION: As Hurricane Irma continues its torrid pace to potentially impact Florida, many people are leaving or in the current stages of planning to leave by plane or by car before the hurricane is forecasted to reach the coast. Locals are not the only ones preparing to leave, however, tourists from central Florida destinations such as Walt Disney World, Universal Studios Florida and Kennedy Space Center are currently trying to re-adjust plans or cancel them outright.
In response to the upcoming hurricane threat, Governor Rick Scott of Florida (R) has suspended all of the tolls to help the evacuations as well as ordered all schools to be closed. Governor Scott has also in advance declared a state of emergency as among the brunt of Irma’s landfall is projected to hit in the metropolis of Miami, Ft. Lauderdale and Palm Beach. This area is forecasted to receive damage costs in the millions or even hitting billions of dollars. In addition to the roads being affected from evacuation, two of South Florida’s airports, Miami International and Ft. Lauderdale-Hollywood International will be hit hard as both are major hubs and focus cities for American Airlines as well as JetBlue, Spirit Airways, and Southwest Airlines. Both airports will likely close as the first band hits as planes there cannot operate in crosswinds greater than 35 mph as well as the tower being forced to close at 55 mph winds. Ft. Lauderdale-Hollywood Airport announced on Thursday that it would be closed starting Friday night. Many airlines have cancelled flights to both airports in preparation for the closures. Some other major areas such as the Orlando, Daytona Beach, and Jacksonville will be hit as well. In these areas, many tourists are rearranging or cancelling their plans as well as trying to evacuate as the area will be hit by the storm. Among the affected regions is the major airport of Orlando International which feeds in most of the tourists to central Florida. The airport announced on Thursday it would close on Saturday at 5 pm in preparation for the storm. The NWS is currently forecasting the winds at the airport to pick up Sunday afternoon with windspeeds near 35 mph at 4 pm which would make it impossible for planes to take off at that time. Meanwhile, Universal Studios and Walt Disney World have not made announcements of whether the parks will close but have posted links about what would happen if people chose to reschedule their trips due to the hurricanes such as cancellation policies. Also, Kennedy Space Center (KSC) had already issued a hurricane condition for employees which has prompted evacuation. NASA has also started to shore up some of the major facilities such as launch facilities, rockets, and the Vehicular Assembly Building. In addition to tourists and locals, many schools and universities will be closed due to the storm including the University of Miami, Embry-Riddle Aeronautic University, University of Central Florida as well as smaller community colleges. Dr. Shawn Milrad, professor of Meteorology at Embry-Riddle, described the Embry-Riddle campus as a ghost town as all the entire campus was closed and the dorms are currently being used for shelters. Milrad also said, “The students at Embry-Riddle especially the meteorology ones are worried especially those from South Florida.” Milrad also included that the meteorology department will have a weather station to track the data of Irma since the station happened to survive Hurricane Matthew the past year. In addition to classes be cancelled, several college football teams across the state are affected. Among the teams affected include the Miami Hurricanes, Florida Gators, and South Florida Bulls all had their games for the weekend cancelled, meanwhile, the Florida State Seminoles and the Central Florida Knights moved their home games to earlier times and dates respectively in anticipation of the storm. To learn more about other high-impact weather events occurring across North America, be sure to click here! ©2017 Meteorologist JP Kalb Terrifying Inferno in the West (Credit: Remote Sensing Applications Center, New York Times)9/7/2017 DISCUSSION: As the southeast United States prepares for a historic hurricane, the western half of the country has been facing their own problems. Particularly in the Pacific Northwest, wildfires have been raging for the past several days, even prompting the governor of Washington to declare a state of emergency. Logan Johnson from the National Weather Service in Seattle says quite ominously, “If you look outside, you might think it’s just clouds.” In most places the air smells of burned wood and the skies have turned a disorienting color of brownish orange. Neither Seattle, Washington nor Portland, Oregon has received any significant precipitation in at least 50 days. In a region known for rain, an unusually dry summer has provided conditions exclusive for wildfires to flourish. A strong ridge of high pressure has settled over the majority of the Pacific Northwest. This has heated the air and prevented storms from entering the area. As a result, places in northern California have experienced record-breaking heat. Trees, grass, and other foliage have dried out, meaning if one small spark occurs then the entire area can quickly be set ablaze. Although precipitation has been absent, winds are still very strong. One of the main concerns now from the fires is ash and smoke, leading to air quality alerts issued in parts of Washington, Oregon, Montana, Idaho, and California. Click here to see the locations of current wildfires in the United States. Click here to see satellite images of the wildfires. The video is taken northbound 210 Freeway in the La Tuna Canyon. This is the largest fire in Los Angeles history. To learn more about high-impact weather events occurring across North America, be sure to visit the Global Weather and Climate Center! ©2017 Meteorologist Nicholas Quaglieri DISCUSSION: There is a big upper level ridge over the Pacific Coast which is increasing temperatures through Labor Day weekend. In addition to the increasing temperatures, the ridge is bringing smoke from fires in Northern California and Oregon into Central California including the San Francisco Bay Area and the San Joaquin Valley. The heat wave is supposed to last through the entire weekend although Sunday seems to be the start of a cooldown from the heatwave as the ridge would slowly moving out easterly. Much of the heat being brought in comes from the very warm Great Basin by the clockwise circulation of the ridge. In addition, there is subsidence (sinking air) occurring along with the planetary boundary layer (PBL) being around 850 millibars in the San Francisco Bay Area which is helping to drive up the temperatures.
On Friday, many records for the month of September across the San Francisco Bay Area was shattered including in San Francisco where the main city reached 106 degrees while San Francisco International Airport had reached a high of 104 degrees. Some of the highest temperatures in the 110s were recorded in locations away from the San Francisco Bay such as Concord. Meanwhile, in the Sacramento and San Joaquin Valleys, temperatures reached the 100s as well and threatened to climb to 110 especially in Sacramento where the high at Sacramento Executive reached a high of 109 during the day. Saturday was a continuation of the heat and daily high records. San Jose had topped up at 107 degrees at the airport while Livermore got warmer by a few degrees. However, some locations were cooler by a few degrees along the coastline but most places remained about the same. In addition to the daily high, the lows were very warm as San Jose bottomed out at 74, San Francisco in the low 70s, while Oakland and Livermore got down into the high 60s. All of which are at least 10 degrees above the normal low temperatures meanwhile the highs were between 20 and 30 degrees above the normal highs according to the climatological reports provided by the National Weather Service. The lows on Saturday were much higher than Friday as a some of the heat was trapped by smoke that was aloft as well as the low PBL and subsidence. The high temperatures and smoke were also factoring into air quality for both areas. In the San Francisco Bay Area, the Bay Area Air Quality Management District issued several consecutive days of “Spare the Air” alerts as well as determining the air quality to be unhealthy especially for sensitive groups. Meanwhile, the air quality district for the Central Valley had also measured the air quality as unhealthy for sensitive groups. To learn more about other high-impact weather events occurring across North America, be sure to click here! ©2017 Meteorologist JP Kalb DISCUSSION: Many people that did not experience the full-force and natural fury associated with the recent U.S.-based landfalls of Hurricane Harvey never fully understood the numbers behind what was left behind in the wake of the recent devastation to a good portion of southeast Texas. Attached below is a great article (courtesy of Meteorologist Gene Norman) which excellently captures the details behind what unfolded with the recent landfalls of Hurricane and then Tropical Storm Harvey in the second of the two U.S. landfalls which occurred.
"I’ve heard that phrase repeated over and over as Hurricane Harvey unleashed historic flooding across southeast Texas and southwest Louisiana. Having lived in Houston for half my life, I am heartbroken to see the people in that great city and the region suffering. So first, I hope that after you read this, you will take a moment to help those in need: http://bit.ly/harvey_help.As a broadcast meteorologist, having assisted people get through the last major storm to hit Houston, Ike in 2008, I have some thoughts on Harvey - specifically on messaging. As in any post-storm assessment, there are things that were done very well and things that can be improved. We in the weather enterprise are a great group and we should be rightly proud of the advancements made in the science of meteorology to detect, analyze and predict threats. However, we tend to be a largely insular group that speaks a common language, but often “talks to itself”. We can quickly recite past storms based on their category, but the general public might not be making these distinctions in the same way. For example, while Harvey was technically the strongest storm to hit the U.S since the last Category 4 storm, Charley in 2004, some were confused at this comparison in the light of Matthew (2016), Sandy (2012) and Katrina (2005). For them, a hurricane’s impact has more meaning than its meteorological designation. Perhaps its time to reconsider the use of a single-number index for classifying a tropical threat and focus more on what will likely happen. If the home page of the National Hurricane Center showed the forecast for the storm along with icons illustrating people on roofs, buildings destroyed and cars floating, that might have conveyed the seriousness of this particular storm. A person in Houston, even a seasoned resident, seeing Harvey’s landfall forecast projection near Corpus Christi, 150 miles away, might not have properly understood that torrential rainfall would fall where they are. Yes, there were predictions of 15, 20 inches or more of rain that were largely consistent on Thursday and Friday. If you’ve lived in Houston, you know – it floods. In fact, you likely know the “usual suspect” flood locations. Past torrents have made traffic treacherous, even deadly and some homes may have taken on water. Few realized that Harvey’s rains were going to produce flooding practically everywhere and many could end up homeless. This despite the repeated use of the word “catastrophic” in numerous forecasts prior to the first drop falling. Compounding the issue was timing and this again points to how important it is to clearly communicate. Leading up to the storm’s arrival, the projection most often shown was of a 30+ inch total over a five-day period, from Friday to the following Wednesday. While this was largely accurate in terms of amount (even though some spots saw an astounding 50 inches), it may have been interpreted as an average of 4 to 5 inches a day for the five-day period. That’s why some many residents and even public officials indicated “surprise” when they awoke to 15 to 20 inches or more Sunday morning and a city largely drowning. Numerous posts from some within the weather enterprise expressed outrage over confusion from anyone about what occurred. We were busy high-fiving ourselves over model forecasts that seemed dead-on, information we assumed the public interpreted the same way. Yet, there was still a disconnect in messaging. Or it could have been something more basic – a simple disbelief. While “we” within the weather enterprise were convinced of the veracity of the forecast based on its consistency, those hearing this information, perhaps including those with public safety authority still might have been slightly skeptical. When I entered broadcasting some twenty-five years ago, I immediately learned an important lesson – “people don’t care how much you know until they know how much you care.” Early in my career, I wanted assure people that I knew what I was talking about. Coaches and others encouraged me to work more on connecting with viewers. Extreme messaging such as the repeated use of the phrases “catastrophic” and “parts of Texas will be uninhabitable” weren’t just hyperbole. Hopefully, lessons learned after Harvey will further move the weather enterprise in a direction that delivers messaging that doesn’t just speak to ourselves but has a greater impact to the end user." To learn more about other high-impact weather events occurring across North America, be sure to click here! ©2017 Meteorologist Jordan Rabinowitz |
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