Most experts adjusted their projections for the 2018 Atlantic hurricane season because one of the primary formation regions has exhibited cooler than normal sea surface temperatures. There has also been some discussion about whether a potentially emerging El Nino (warmer than normal sea surface temperatures in the eastern Pacific Ocean) will impact activity. Even with these circumstances, it is important to remember that it only takes “one” hurricane to significantly impact society so it is important to pay attention. Hurricane Beryl has formed, and there are a few interesting things about it.
Beryl is the first hurricane of the 2018 Atlantic season. I have to admit Beryl escalated rather unexpectedly from my vantage point. I am normally very weather-attentive but have been exploring the spectacular national parks with my family the past 8 days. Here are the specific details of Hurricane Beryl from the National Hurricane Center as of the morning of July 6th, 2018:
The cyclone has another 18-24 hour within very low vertical wind shear conditions and over SSTS of 26-27 degrees Celsius. These favorable conditions suggest that the tiny hurricane is likely to intensify further today. The NHC intensity forecast calls for additional strengthening and is at the upper-end of the intensity guidance
As noted, Beryl is a rather compact storm but has the potential to pack a little punch because of intensity projections. The key messages from the National Hurricane center are that there is great uncertainty in the intensity forecast. If you recall from a previous piece I wrote in Forbes, intensity forecasts are typically more difficult than track forecasts. Irrespective of track, the islands of the Lesser Antilles should be on alert as the current forecast has it reaching them as a tropical storm even though there is a possibility that it could weaken by then too. It is expected move into stronger wind shear conditions (red in the graphic below). Stronger wind shear tends to disrupt the formation of the the hurricanes, but I advise that we not let our guard down because other factors could offset the shear. By the way, you will often see the term “favorable” used to describe good conditions for hurricane formation. I choose not to use that term because to me there is nothing favorable about a hurricane getting stronger. As I posted this piece, the National Weather Service’s National Hurricane Center noted that winds in Beryl were up to 80 mph winds, which is fairly significant for a July storm.
What are my fellow meteorologist colleagues saying about Hurricane Beryl? According to a Tweet by tropical meteorologist Dr. Phil Klotbach of Colorado State University, Beryl is the “2nd earliest calendar year hurricane in the tropical Atlantic (<20°N, 60-20°W) on record, trailing only 1933.” Meteorologist Greg Diamond provides some interesting context on the size of Beryl. He tweets, “Some perspective on just how small Beryl is. Tropical storm winds only extend out 35 miles from the center.” Brian McNoldy also provides an interesting statistic in his tweet, “Of the 89 pre-August hurricanes on record, #Beryl is the easternmost among those that formed from African waves… by a HUGE margin!”
While much of the tropical Atlantic has been cool this season, Beryl has formed in a region of sea surface temperatures (SSTs) warm enough to support tropical development. The graphic of SSTs provided by CIMMS at the University of Wisconsin provides context. Waters typically need to be at least 26.5 deg C (80 deg F) for hurricanes to form.
Oh and by the way, the National Hurricane Center is also watching a low pressure system a few hundred miles off the coast of North Carolina. There is 70-80 percent chance that this system may develop into a tropical depression within the next 2 to 5 days. Hurricane expert Dr. Michael Ventrice of IBM and The Weather Company even kept the door open for it to develop into a tropical storm or hurricane. He tweeted,
Still low, though the chance of Tropical Storm Force winds is increasing with time for Cape Hatteras due to the genesis risk of invest
#96L. There is some risk this storm develops into a Hurricane intensity as it recurves across the warm sub-tropical Atlantic waters……..Our Calibrated ECMWF EPS is bullish on the idea that we will see two tropical cyclones spinning simultaneously across the Atlantic within the next 24-48 hours. Watch for NHC update today/tomorrow.
If you are in the Carolinas, you may want to keep an eye on this storm too.