Blogs

This year, especially this last quarter, has been a tough one on the weather and climate front. With that said, one silver lining of a rough 2017 has been the general retreat of drought on a national scale. This spring, according to the U.S. Drought Monitor, the fraction of the contiguous United States in drought dropped below 10 percent for the first time since 2010. However, with that said, since then, a severe drought emerged quickly in the Northern Plains this summer. As droughts go, this was a “flash drought”—rapid-onset, regional drought, driven by combination of factors, typically during the summer. The early impacts of this drought episode were covered here on Climat…   Read article

You may be thinking “There are even more things that forecasters look at when making seasonal forecasts?” or “Haven’t you already written about those other things, multiple times?” And the answer to both of those questions is yes. But what if I told you that there is another mysterious thing that, at least for seasonal temperature outlooks, gives forecasters a better idea of what will happen than predictions of ENSO or the Madden Julian Oscillation, or the Arctic Oscillation or the North Atlantic Oscillation or the Pacific Decadal Oscillation or…I think you get the point (1). And it’s much simpler than all of those. It’s called the trend. Cool, another vaguely science sounding term. W…   Read article

The climate of the islands of Hawaii and the Pacific is often characterized by iconic scenes of warm, sandy beaches, blue skies, and swaying palm trees.  However, these scenes can be dramatically transformed when sea levels become anomalously high or low, wave action increases due to nearby storms, and drought or heavy rains impact local food supplies.  In other words, there can be climate trouble even in paradise. Most regions of the United States fall within major land areas, and their weather and climate are well observed by ground-based stations. However, the tropical Pacific spans thousands of miles on end without land, and this geography makes it difficult to collect weath…   Read article

The September ENSO forecast is out!! (Can you tell I’m excited to be back on the top-of-the-month post?) Forecasters think there is an approximately 55-60% chance of La Niña this fall and winter, so we’re hoisting a La Niña Watch. Read on to find out what’s behind this development! Summer summary First, though, a quick recap of current conditions in the tropical Pacific Ocean. The sea surface temperature in our favorite Niño3.4 region in the central Pacific was about 0.1°C colder than the long-term average over June – August, smack-dab in the neutral range. The atmosphere also reflected neutral conditions during the summer, with the winds above the equatorial Pacific neither particular…   Read article

It’s been a tough few weeks weather and climate wise. Big events generate lots of questions, so this edition of Beyond the Data will address several I’ve heard recently, and several I asked myself. Was Harvey’s rainfall really record-breaking? It appears so, at least for the contiguous United States, from the perspective of “How much rain fell into a single official rain gauge over the course of a single tropical storm?” There is no official record for tropical cyclone, as far as the National Climate Extremes Committee has vetted, but the National Weather Service keeps an online resource listing peak rains for almost all named storms since 1950, and a few before that. Comparing tota…   Read article