WEEKLY WEATHER AND CLIMATE NEWS

15-19 July 2019

Items of Interest:

• Hurricane awareness week in New England and interior New York State -- During week of 14-20 July 2019, the six New England states will observe New England Hurricane Awareness Week. Sections of interior New York State outside the New York City metropolitan area will also schedule Hurricane Awareness activities.
• Zenithal Sun -- Residents of Honolulu will experience a noontime sun that would be directly overhead during this week (15-17 July). This occurrence of a zenithal sun is one of the two times during the year when the noontime sun is directly overhead to residents of Honolulu and the Hawaiian Island of Oahu. The other time when Oahu experienced a zenithal sun was in late May. [US Naval Observatory, Data Services]
• Celebrating the 50th anniversary of the Apollo 11 landing on the Moon -- This Saturday, 20 July, will mark the 50th anniversary of the date when Commander Neil Armstrong and lunar module pilot Buzz Aldrin became the first two humans to step on the surface of the Moon. They walked on the lunar surface approximately six hours after the Apollo 11 Lunar Module Eagle touched down in the Sea of Tranquillity at 2017 Z (4:17 PM EDT or 3:17 PM CDT, etc.). NASA will be celebrating the event with live TV broadcasts and other events.

Weather and Climate News items:

• Eye on the tropics -- During the last week, several tropical cyclones were reported across the eastern North Pacific and the North Atlantic basins:
• In the eastern North Pacific basin, Tropical Storm Cosme had weakened to a tropical depression at the start of last week as it was traveling to the northwest away from the western coast of Mexico. By last Monday morning, Tropical Depression Cosme was encountering a hostile environment of dry air, cool sea water and wind shear, which caused Cosme to degenerate into a post-tropical remnant low with maximum sustained winds of 30 mph. At that time, this remnant low was located approximately 710 miles to the west of Cabo San Lucas, which is located at the southern tip of Mexico's Baja California Peninsula. A satellite image and additional information on Tropical Storm Cosme can be found on the NASA Hurricane Blog.
  The fourth tropical depression of 2019 in the Eastern Pacific basin, identified as TD-4E, formed last Friday afternoon approximately 340 miles to the southwest of Manzanillo, Mexico. Over this past weekend, TD-4E traveled generally toward the west-northwest, but never gained sufficient strength to become a tropical storm as estimated maximum sustained surface winds remained at approximately 35 mph. On this past Sunday morning, TD-4E was downgraded to a remnant low as winds dropped to 30 mph. At that time, this remnant low was located approximately 485 miles to the southwest of Cabo San Lucas, Mexico, as it continued to travel toward the west-northwest, away from the Mexican coast. Apparently, dry air and sufficient wind shear across the region prevented further intensification.
• In the North Atlantic basin, a diffuse area of low pressure traveled southward across several Southeastern States last week before moving off the coast and out over the northeastern Gulf of Mexico. While over the warm waters of the Gulf, this low organized and strengthened to become Tropical Storm Barry last Thursday morning, as maximum sustained surface winds reached 40 mph. Barry is the second named tropical cyclone of 2019 in the North Atlantic basin that includes the Gulf of Mexico and Caribbean Sea. At that time, the center of Tropical Storm Barry was moving toward the west and was located approximately 95 miles to the south-southeast of the mouth of the Mississippi River. Barry continued traveling toward the west offshore of the Louisiana coast on Thursday, before gradually curving toward the west-northwest on Friday. Intensification was occurring with a drop in central air pressure and a corresponding increase in surface wind speeds. On Saturday morning, the center of Tropical Storm Barry began to curve toward the northwest and by mid-morning, the maximum sustained surface winds reached 75 mph, making Barry the first Atlantic hurricane of 2019. At that time, Hurricane Barry was approaching the Louisiana coast, approximately 40 miles to the south of Lafayette and 50 miles west of Morgan City. Approximately three hours later, Hurricane Barry was downgraded to a tropical storm as it was making landfall approximately five miles northeast of Intercoastal City, LA. Moving inland across Louisiana on Saturday and into Sunday, Tropical Storm Barry weakened slowly as it curved toward the north-northwest and then to the north. By late Sunday afternoon, Barry had weakened to a tropical depression as it was passing northward approximately 20 miles to the north-northeast of Shreveport, LA. Surface winds had subsided to 35 mph. Barry was forecast to weaken to a remnant low by Monday evening. Through much of its life, Barry subjected the north-central Gulf Coast of Alabama, Mississippi and Louisiana to torrential rains along with strong and potentially damaging onshore winds that were also responsible for a dangerous storm surge. The NASA Hurricane Blog has additional information and satellite images for Tropical Storm Barry.
• National weather and climate reviewed for June 2019 -- Scientists at the NOAA National Centers for Environmental Information (NCEI) recently reported on their analysis of preliminary weather data collected during the month of June 2019. They found:
• The monthly temperature averaged across the coterminous United States for that month was 68.7 degrees Fahrenheit, which was 0.2 Fahrenheit degrees above the 20th-century (1901-2000) June average. Consequently, this past June ranked near the middle of June temperatures since 1895 when comprehensive climate records became available nationwide; the nationwide average temperature for June 2019 was the 61st highest (or 65th lowest) in the 125-year period of record. The majority (30) of the 48 contiguous United States reported near-average monthly temperatures for June 2019. Eleven states along the East and West Coasts had statewide temperatures that were above to much above-average. Florida reported its third highest June average temperature in 125 years, while Delaware experienced its ten highest June temperature. On the other hand, seven states had below-average June temperatures; these states stretched from Colorado eastward to Arkansas and across sections of the Midwest and the Northeast.
  The maximum (or daytime) temperature for June the 48 contiguous United States was 0.2 Fahrenheit degrees below the 20th century average, which makes this temperature the 55th lowest in 125 years. The minimum (nighttime) temperature for the "Lower 48" was 0.6 Fahrenheit degrees above the 20th century average, which was the 51st highest minimum June temperature on record. Florida had its highest statewide minimum temperatures on record.
  The June 2019 statewide average temperature for Alaska was 54.0 degrees, which is the second highest in the state's period of record that extends back to 1925.
• The nationwide average precipitation for June 2019 was 3.30 inches, which was 0.37 inches above the 20th-century average, making this past month the 27th wettest June in 125 years. A large number of the states to the east of the Rockies (25) had statewide precipitation totals that were above to much-above the long-term average. Kentucky reported its third wettest June in 125 years, Ohio its fifth wettest and Tennessee its eighth wettest. Conversely, eight states across the northern Plains and the West (stretching from the Intermountain West to the West Coast) had below-average precipitation. The remainder of the states (15) in the "Lower 48" had precipitation totals that were close to the long-term average.
  This past June was the nineteenth driest in Alaska for the last 95 years.
NOTE: A description is provided of the climatological rankings employed by NCEI for their monthly and seasonal maps. [NOAA/NCEI]
• A map entitled "Map of U.S. Selected Significant Climate Anomalies and Events for June 2019" graphically summarizes several significant weather and climate events that occurred across all 50 states and Puerto Rico during June.
[NOAA NCEI State of the Climate]
• Another national 12-month precipitation record is set -- NCEI scientists recently reported that the average precipitation across the contiguous U.S. for the 12-month interval running from July 2018 through June 2019 was 37.86 inches, which was 7.90 inches above average. This national precipitation total set a new record, exceeding the previous all-time 12-month period of 37.72 inches that occurred from June 2018 to May 2019 Interestingly, the record set in June marks the third consecutive time in 2019 that a record has been broken, as the previous record set at the end of May had broken the prior all-time 12-month record of 36.31 inches between May 2018 and April 2019. [NOAA News]
• June national drought report -- The National Centers for Environmental Information has posted its June 2019 drought report online. Using the Palmer Drought Severity Index, approximately one percent of the coterminous United States experienced severe to extreme drought conditions at the end of June, while 49 percent of the area had severely to extremely wet conditions.
• Historic Alaskan heat wave exacerbates wildfires -- A dome of unseasonably warm air became established over Alaska in late June and has remained across the 49th State, leading to a series of record breaking high temperatures at several locations. On the 4th of July, the temperature at Anchorage soared to 90 degrees, which is the highest temperature ever recorded in the state's largest city. In addition to causing an unseasonably warm spell, the high pressure ridge has resulted in relatively dry conditions, which has resulted in wildfires. A natural color image made from data obtained by the MODIS sensor onboard NASA's Aqua satellite on Friday, 5 July shows the widespread smoke drifting across southern Alaska. [NASA Earth Observatory]
• Extreme rain events appear to be increasing across the nation -- A feature prepared for NOAA's ClimateWatch Magazine investigates the increase in frequency of extreme precipitation events across the 48 contiguous states since the start of the twentieth century. Excessive precipitation events have been defined in this instance as those occurrences of heavy rain or snow that rank among the top one percent (99th percentile) of daily events. National maps are provided that show the observed long-term changes in extreme precipitation between 1901 and 2016, along with observed recent changes running from 1958 through 2016. These maps were obtained from the Fourth National Climate Assessment (NCA4). Furthermore, such events are likely to become even more frequent over the remainder of the 21st century, as indicated by national maps showing projections based upon climate models run for both low and high greenhouse gas emissions scenarios. [NOAA Climate.gov News]
• Role of atmospheric rivers in future precipitation regime change across the West is clarified -- Scientists associated with the NOAA-funded California-Nevada Applications Program recently published an article that explains the dominant mechanism for projected intensification of extreme precipitation in California and Western North America. While daily precipitation in California is expected to decrease in the future due to a warming climate, an intensification of excessive or extreme precipitation events appears to be associated with the intensification of atmospheric rivers in that warmer climate. The atmospheric rivers are long bands of water vapor and clouds being carried across the North Pacific in the mid and upper troposphere from subtropical latitudes and onto the West Coast of North America, where orographic lifting over the Western Cordillera results in abundant precipitation. In addition, interannual variability of total annual precipitation was expected to increase. [NOAA Climate Program Office News]
• Updated El Niño/Southern Oscillation (ENSO) Diagnostic Discussion is released -- Forecasters at NOAA's Climate Prediction Center (CPC) and the International Research Institute for Climate and Society (IRI) released their monthly El Niño/Southern Oscillation (ENSO) Diagnostic Discussion late last week. They reported that above-average sea surface temperatures (SST) continued through June 2019 across the central equatorial Pacific Ocean. However, the SST anomalies (differences between observed and long-term average SSTs) were decreasing across most of the eastern Pacific. In addition, anomalously cool waters were also expanding at depth. In the lower atmosphere, wind anomalies were close to average. In addition, other oceanic and atmospheric conditions were suggestive of a weakening El Niño. The prediction models used by the forecasters indicate a transition from El Niño to ENSO-neutral conditions by the Northern Hemisphere summer (June, July and August), followed by the continuation of neutral conditions through the boreal autumn and winter (September 2019 through February 2020). (An ENSO-neutral situation is one with neither El Niño nor La Niña conditions prevailing.) Therefore, the forecasters have continued an El Niño Advisory as part of the CPC's ENSO Alert System Status, since they maintain that the transition from El Niño to ENSO-neutral is expected within the next one to two months. Additional information is available for this alert system involving these El Niño/La Niña watches and advisories.
  [NOAA Climate Prediction Center]
• An El Niño forecast from Down Under -- Forecasters with the Australian Bureau of Meteorology recently issued an updated ENSO forecast, in which they reported ENSO-neutral conditions, with both the oceanic and atmospheric components of the tropical climate system tending to be close to normal conditions. They note that the latest model outlooks indicate that the likelihood of ENSO conditions forming in Southern Hemisphere winter (June-August) and continuing through spring (September-November). Therefore, they have declared the Bureau's ENSO Outlook to be "INACTIVE." [Australian Government Bureau of Meteorology]
• Updated Atlantic hurricane season outlook foresees near average activity in 2019 -- Philip Klotzbach and fellow hurricane forecasters at Colorado State University, issued their updated July forecast for the 2019 Atlantic hurricane season that contained little change to their June forecast, which was slightly higher than their April outlook. In their newly issued forecast, they foresee average tropical cyclone activity. Their current outlook for the number of named tropical cyclones (hurricanes and tropical storms with sustained surface winds of at least 39 mph) remains at 14. This number includes Subtropical Storm Andrea that formed over the central North Atlantic in mid to late-May, but does not include Tropical Storm Barry, which formed over the Gulf of Mexico after the new July outlook was posted. Their number of anticipated hurricanes (maximum sustained winds of 74 mph or higher) remains at six and their number of projected major hurricanes (category 3 or higher on the Saffir-Simpson Scale) would remain at two. They consider the probability for major hurricanes making landfall along the United States coastline and in the Caribbean also to remain near average. The forecasters note that waters in the tropical and subtropical North Atlantic continue to exhibit near average sea surface temperatures and that the odds for a weak El Niño persisting through the peak in the Atlantic hurricane season (August through October) have diminished. The team will issue one final pre-season outlook for 2019 during the first week of August.   [The Tropical Storm Project]
• Urban heat island mapping campaigns are slated for eight U.S. cities this summer -- Community organizers in eight U.S. cities are preparing to run citizen-science field campaigns that are designed to map urban heat islands (UHI) this summer. The National Integrated Heat Health Information System (NIHHIS) and the NOAA Climate Project Office's Communication, Education, and Engagement Division. Cities were selected for support that was based in part on their readiness to mobilize community members to run the mapping campaign and on their ability and willingness to use the heat maps produced by the campaign to build resilience to extreme heat. The eight cities selected for 2019 h, Ft. Lauderdale and Miami, FL; Yonkers, NY; Seattle, WA; and Honolulu, HI. National Weather Service personnel, NIHHIS collaborators and Weather Ready Nation Ambassadors in each city will be involved in helping identify high-heat target dates and publicize the campaigns. [NOAA Climate Program Office News]
• List of nation's billion-dollar weather & climate disasters updated for first half of 2019 -- NOAA's National Centers for Environmental Information recently updated its "U.S. Billion-Dollar Weather & Climate Disasters 1980-2019" through the first week of July 2019. This updated list includes six weather and climate disaster events with losses exceeding $1 billion each across the United States during the first six months of 2019. These events consisted of two flooding events and four severe storm events involving tornadoes, damaging straight-line thunderstorm winds and large hail. Overall, these six events in 2019 resulted in the deaths of 15 people along with the significant economic effects on the areas impacted. [NOAA/NCEI]
• National Hurricane Center releases its forecast verification report for 2018 -- NOAA's National Hurricane Center (NHC) released its 73-page Forecast Verification Report for the 2018 hurricane season in the North Atlantic and eastern North Pacific basins last month. NHC issued 390 official forecasts for the North Atlantic basin since the 2018 hurricane season had above-normal activity for that basin. The official NHC track forecasts in the Atlantic basin were successful in 2018, being close to the mean NHC official track forecast errors for the previous 5 years at most forecast times. However, mean official intensity errors for the Atlantic basin in 2018 were lower than the 5-year means at most forecast times.
  NHC issued 450 official forecasts for the eastern North Pacific basin, which were above average, and the most forecasts issued since 1992. Although the forecasts where skillful, no records for track accuracy were set in this basin in 2018. Official intensity forecast errors in the eastern North Pacific basin were higher than the 5-year means at all forecast times. [NOAA National Hurricane Center]
• Report made on recurrent "nuisance" coastal flooding across nation during 2018 -- Scientists from NOAA's Center for Operational Oceanographic Products and Services and from NCEI recently prepared a 31-page annual report entitled "2018 State of U.S. High Tide Flooding and a 2019 Outlook" that provides a review of the state of recurrent coastal tidal flooding in the U.S. considered "nuisance flooding." Nuisance flooding is defined as a situation when a water level measured at a NOAA water level gauge exceeds the local elevation threshold for minor impacts. The report indicates that in the 2018 meteorological year running from May 2018 through April 2019 the national annual high tide flooding frequency at 98 NOAA tide gauges reached a median value of five days, which tied the historical record set in 2015. Locations along the Northeast Coast of the U.S. experienced the most high tide flooding, with a median value of ten days, while record numbers were reported along Chesapeake Bay. Major flooding was reported along the eastern Gulf of Mexico coast due to several hurricanes, with a median number of five days. Twelve of the 98 tide gauges either tied or broke their annual high tide flooding records during 2018. Furthermore, the decadal high tide flooding trends at more than 40 tide gauge sites have experienced a nonlinear increase that is considered to be a significant acceleration, while 25 locations have had linear increases. The portion of the report focusing upon the outlook for this upcoming year ending in April 2020 indicates that the frequency of daily flooding is expected to increase because of anticipated El Niño conditions and from long-term sea level rise trends. The forecasters envision between seven and fifteen days in high tide flooding by 2030. [NOAA News]
• A large harmful algal bloom is predicted this summer for western Lake Erie -- Late last week scientists from NOAA and the partner institutions of Ohio Sea Grant, Ohio State University, Ohio's Heidelberg University and University of Michigan predict a significantly large harmful algal bloom in western Lake Erie for summer 2019. This final version of their 2019 seasonal forecast involves the generation of a severity index, which is based upon the amount of the expected bloom's biomass. The numerical models used in producing the forecast involve assessing and predicting the nutrient runoff. Coastal water color data obtained from the European Copernicus Sentinel-3 satellite are used in the model. The severity index is expected to reach 7.5, but could range between 6 and 9. The record 2015 bloom has an index of 10.5, followed closely by 2011, when the index reached 10. For comparison, 2018 had a severity index of 3.8. The anticipated significant algal bloom for 2019 is due to the recent wet spring that enhanced the flow of nutrients into lake, which provided fuel for algal growth. The bloom was expected to commence in late July because the above average spring precipitation has caused lake waters to remain relatively cool. The eastern end of Lake Erie should not experience algal bloom. [NOAA News]
• Public opinion on future NOAA R&D priorities is solicited -- NOAA is requesting its stakeholders and the general public for their comments on a new draft plan that outlines agency priorities for research and development (R&D) from 2020 to 2026. This NOAA R&D draft outlines three key overarching priorities:
  --Reducing societal impacts from severe weather and other environmental phenomena
  --Sustainable use and stewardship of ocean and coastal resources
  --A robust and effective research, development, and transition enterprise
  Public comments can be submitted via email until 26 August 2019. [NOAA Research News]
• An All-Hazards Monitor -- This Web portal provides the user information from NOAA's National Weather Service, FAA and FEMA on current environmental events that may pose as hazards such as tropical weather, fire weather, marine weather, severe weather, drought and floods. [NOAA/NWS Daily Briefing]
• Earthweek -- Diary of the Planet [earthweek.com]