05/07/2023, 7:52 pm EDT

U.S. Selected Cities CDD Forecast for 2023

05/04/2023, 11:20 am EDT

U.S. Gas Population Weight HDD Forecast for Oct-22 to Apr-23 FINAL/Verification

05/03/2023, 8:39 am EDT

Europe Month 1-4 Ahead/Summer 2023 Outlook: Regenerating important heat/dryness is likely (again) during summer of 2023.

Executive Summary: The Europe/Western Russia month 1-4 ahead outlook valid through September 2023 indicates more heat and dryness for Europe ahead. The meteorological summer 2023 forecast indicates widespread anomalous warmth for Europe, the Black Sea region, and across the Caspian Sea. Despite wet soils to start the warm season across Central/East Europe, a drier than normal summer climate is ahead. Dryness is also likely across the eastern Black Sea/Caspian Sea region. Evolution of a marine heat wave off Northwest Africa could enhance the very warm/dry climate forecast if this feature persists. The evolving drought that follows this hot/dry forecast is not as severe as last year except for South-central/Southwest and Northern Europe. Fig. 1-2: The Climate Impact Company constructed analog climate forecast of temperature and precipitation anomalies for Europe/Western Russia for JUN/JUL/AUG 2023. Climate: The Europe/Russia season 1-3 ahead climate forecast is based on development of positive phase Indian Ocean Dipole (+IOD), evolving El Nino, and optimum climate normal (OCN) featuring the 10-year climatology. During the 2023 warm season, +IOD develops according to Australia Bureau of Meteorology. When +IOD is in-place, the warm SSTA pattern in the western tropical Indian Ocean fuels thunderstorm activity. Latent heat release from that convection released poleward and on average leads to an enhanced subtropical high-pressure system just east of the Black Sea which causes increased anomalous hot and dry climate risk. To compensate for the ridge, an intense trough forms to the north across Northern Russia during summertime. The +IOD analog years are 1997, 2006, 2012, and 2015. This pattern weighs heavily on the warm season outlook for Europe and Western Russia. The +IOD pattern considered for autumn weakens by late year and is not part of the winter 2022-23 outlook. El Nino arrives during the next 1-2 months. The intensity level is uncertain. There is about equal risk of a weak or strong El Nino developing during the middle third of 2023. Later this year a stronger El Nino is likely. To cover an organized El Nino climate risk for Europe/Western Russia, added are analog years 1997 and 2015. The influence on Europe climate by an oncoming El Nino is a wet bias for far southern areas and drier/warmer than normal with latitude. Finally, the persistence and influence on climate to the northern hemisphere by the Northeast Pacific marine heat wave (MHW) and North Atlantic warm hole (NAWH) beginning in 2014, an optimum climate normal (for 2014-22) are considered for the forecast. On average, the OCN climate influence on Europe during the warm season is drier/warmer than normal for Central Europe to Ukraine. In addition, MHW activity is evolving off the northwestern coast of Africa and southwest of Europe. The attendant high-pressure ridge is causing early season heat and promoting drought in Northwest Africa/Southwest Europe. If this feature continues to evolve adjustments to the forecast may be necessary biased toward more dryness and heat for Southwest Europe extending northward with time. June 2023: The early meteorological summer outlook indicates developing anomalous heat centered on the Caspian Sea region. Anomalous heat also evolves across South-central Europe and expands northward during the month. The MHW off the Northwest Coast of Africa could bias this anomalous heat and dryness farther west. The precipitation forecast is confident with wet weather centered on Western Turkey but could be drier in France due to the Northwest Africa MHW and attendant upper ridge pattern. Central and Northern Europe are drier than normal. Fig. 3-4: The Climate Impact Company temperature and precipitation anomaly forecast for June 2023 across Europe/Western Russia. July 2023: Upper ridge pattern brings a hot and dry mid-summer to much of Europe. Downstream the upper ridge location, an equally impressive upper trough cools Northwest Russia. The upper trough may produce mid-summer thunderstorm activity affecting parts of Western Russia and the Black Sea region. Fig. 5-6: The Climate Impact Company temperature and precipitation anomaly forecast for July 2023 across Europe/Western Russia. August 2023: Late meteorological summer emphasizes a high latitude upper ridge pattern leaving the northern 2/3 of Europe drier and hotter than normal. The dryness and anomalous heat spreads into Southwest Russia and the Black Sea region. Southern Europe is also warmer than normal although wet weather threats are possible for Southeast Europe. The NAWH upper trough budges eastward to bring late summer rains to U.K. Fig. 7-8: The Climate Impact Company temperature and precipitation anomaly forecast for August 2023 across Europe/Western Russia. September 2023: The upper ridge shifts southward causing the dry climate to shift while all of Europe and into Western Russia is likely to remain warmer than normal. Fig. 9-10: The Climate Impact Company temperature and precipitation anomaly forecast for September 2023 across Europe/Western Russia.  
04/19/2023, 5:09 pm EDT

U.S. Season 1-3 Ahead Climate Outlook: Risk of a central North America high-pressure ridge for summer 2023, autumn is wet, next winter is potentially (stormy/cold) interesting.

Executive Summary: The North America season 1-3 ahead climate forecast is valid for meteorological summer and autumn 2023 and adding winter 2023-24. Highlights include increasing risk of an upper-level ridge over central North America during summer 2023 as the Central U.S. forecast trends hotter/drier. Most of the U.S. is warmer than normal during summer. The central/southwest Great Plains to Texas drought may expand northeastward during summer before a wet autumn suppresses the dryness. The Texas drought erodes. Next winter looks cold in the Central U.S. and stormy for the East States. Winter 2023-24 could be interesting as an El Nino Southwest U.S. trough develops and combines with a blocking high pressure area over Greenland causing more widespread cold and storminess. Climate: The North America season 1-3 ahead climate forecast is based on projected regional sea surface temperature anomaly (SSTA) regimes such as El Nino southern oscillation (ENSO), Pacific decadal oscillation (PDO), Atlantic multi-decadal oscillation (AMO), and marine heat waves plus current soil moisture analysis and trend. The ENSO forecast into 2024 anticipates El Nino. The last El Nino was observed in 2018-19 and was relatively weak. The last full-throttle El Nino occurred in 2015-16 and rivaled the 1997-98 and 1982-83 El Nino episodes as the strongest on record. Currently, dynamic models are projecting a strong El Nino for the second half of 2023 similar in intensity to the historic 2015-16, 1997-98, and 1982-83 warm ENSO events (Fig. 1). However, statistical models (based on analogs), favor a weaker El Nino (Fig. 2). Climate diagnostics reveal a steady trend toward a stronger El Nino as the northwest coast of South America is prohibitively warm and the equatorial subsurface East Pacific is warming sharply. However, the new presence and influence of the northeast Pacific marine heat wave (MHW) is a governing force on ENSO especially if a 2015-16 El Nino is to form (Fig. 3). The 2013-2023 semi-permanent northeast Pacific MHW budged westward and away from the North America West Coast the past 3-6 months allowing the waters off the West Coast to cool during the 2022-23 cold season and the cool SSTA regime remains in-place (Fig. 4). For El Nino to develop as strongly as indicated by the C3S/ECM projection for August 2023 (Fig. 5), the MHW will need to shift eastward back to the North America West Coast. The C3S/ECM (dynamic) model does not indicate that scenario as of JUL/AUG/SEP 2023. Consequently, El Nino 2023 will develop but not as strongly as dynamic models indicate but more intense than the weaker analog solutions. Fig. 1-2: The NCEP CFS V2, similar to other ENSO forecasts, is forecasting an intense El Nino for the second half of 2023. Meanwhile, analog forecasts such as the Climate Impact Company constructed analog indicate weaker El Nino. Fig. 3-4: The last strong El Nino was in 2015 when the northeast Pacific coastal region was also very warm (left). Currently, the coastal Northeast Pacific is cool and the California Ocean Current circling southwestward to the south of Hawaii is blocking western progress of El Nino warm waters off the northwest coast of South America. Fig. 5: The C3S/ECM global SSTA forecast for JUL/AUG/SEP 2023 keeps the MHW off the Northeast Pacific coast suggesting the El Nino forecast may be too strong. The North Atlantic is quite warm except for the North Atlantic warm hole (NAWH) south of Greenland. The northeast quadrant of the North Pacific contains the MHW and the much cooler regime off the West Coast which is a classic cool phase. The -PDO regime is entering a 4th consecutive year. The CS3/ECM global SSTA forecast indicates the -PDO regime weakens but does not end during Q2/2023. A transition to a weak warm phase for the 2023-24 cool season is likely. Normally, PDO and ENSO phase run parallel. A stronger El Nino requires PDO shift into the warm phase. An aggressive warmer than normal forecast for the North Atlantic basin is projected by the CS3/ECM model. The warm SSTA involves both the North Atlantic basin and deep tropics. Forecast confidence is increasing on expectations of a moderate (or stronger) warm phase of both the AMO and tropical North Atlantic (TNA) patterns. The TNA index calculates SSTA in the ocean region east of the Caribbean Sea to the northwest coast of Africa also known as the main development region (MDR) for hurricanes. Climate Impact Company indicates a weaker El Nino forecast (compared to dynamic models) for tropical cyclone season and combined with a vigorously warm North Atlantic SSTA regime, the seasonal forecast of 12 storms, 7 hurricanes, and 3 intense hurricane is a little stronger than El Nino climatology. Since 2013-14, the MHW pattern in the northeast Pacific Ocean has not only been dominant but also having a consistent influence on climate by producing a semi-permanent upper-level high-pressure ridge oscillating from the North America West Coast or offshore in-between Hawaii and Alaska. This feature will continue through next winter having (great) influence on the western North America climate pattern with residual downstream effects. Similarly, the accelerated ice and snow melt in the northern Atlantic including the Greenland ice sheet has caused a cool pool of water to persist in the Labrador Sea to south of Greenland where the North Atlantic warm hole (NAWH) exists. Since 2013-14, the NAWH pattern has forced a semi-permanent upper trough across this region compensated for by persistent upper-level high-pressure ridge areas in eastern North America and Europe. The NAWH pattern is responsible for milder winters in East North America and Europe during the past 10 years (Fig. 6). and increases risk of stronger hurricanes in the western North Atlantic basin as the NAWH regime blocks the Gulf Stream forcing the piling of warm water off the U.S. East Coast. The NAWH regime continues through next winter. Finally, having a significant influence on the warm season climate, is the tendency for high-pressure ridging to form across or downwind of a large drought area while low pressure suppressing summer heat risk is generally present across wet soil moisture regions. In the U.S., a major drought has evolved across the central and southern Great Plains to Texas and Florida plus the Mid-Atlantic region (Fig. 7). The trend of soil moisture as mid-spring approaches is drier in the drought areas mentioned except wetter in Florida and coastal Texas (Fig. 8). After a wet winter season in California and the end of long-term drought, the recent soil moisture trend is drier as the wet soil regime in that region is likely to weaken heading into summer. The key zones are the central and southern Great Plains plus the Mid-Atlantic region as a heat enhancer for summertime ahead if the drought remains intact. Fig. 6: A dominant feature causing North America and Europe climate during 2014-22 (and continuing in 2023) is presence of the marine heat wave in the northeast Pacific and North Atlantic warm hole and the influence on the upper air pattern. Fig. 7-8: Current U.S. soil moisture anomalies and the change in April (so far). Forecast methodology: The climate diagnostics discussed generate the season 1-3 ahead climate forecast for North America. In review, the influence of an evolving El Nino, slowly weakening cool PDO, strengthening AMO, and persistent northeast Pacific MHW and NAWH south of Greenland are each heavily weighted to produce a constructed analog. The soil moisture regime is considered for the warm season (only). The prevailing upper air forecast: The Climate Impact Company constructed analog (CIC-CA) forecast projects an upper-level high-pressure ridge centered over central North America for summer 2023 (Fig. 9). As a result, the North-central U.S. trend is drier and warmer. The primary influence of the ridge is to trend the U.S. hotter for meteorological summer. Unusual for the 10-year climatology is presence of an upper trough north of Hawaii as projected for autumn 2023 (Fig. 10). The upper ridge associated with the northeast Pacific marine heat wave shifts north and over Alaska. Downstream from the upper ridge extending along the North America West Coast is an upper trough in the East-central U.S. which produces shear to prevent hurricanes from roaming the northern half of the Gulf of Mexico. The upper air pattern projected for winter 2023-24 features the classic El Nino low latitude trough across the Southwest U.S. coupled with blocking high pressure over Greenland (Fig. 11) implying a potentially stormy winter ahead with copious snow. Fig. 9-11: The Climate Impact Company upper air forecast for meteorological summer and autumn 2023 plus winter 2023-24. JUN/JUL/AUG 2023: The meteorological summer forecast trend is hotter and drier in the U.S. Corn Belt. The West U.S. to Texas remain hotter than normal. The Northeast remains very warm and humid for summer 2023. The precipitation outlook manages to stay wet in the Mid-Atlantic to New England stretch and much of the Gulf region especially near the coast. The upper air projection indicates much of the Gulf Coast rain is synoptic scale and not tropical cyclone oriented. The central Great Plains drought entering the summer season persists and may yield hotter than forecast results in that region and vicinity. Fig. 12-13: The Climate Impact Company upper air/temperature/precipitation anomaly climate forecast for JUN/JUL/AUG 2023.  SEP/OCT/NOV 2023: The West/Southwest and East remain warmer than normal for the autumn forecast. However, a cooler trend projects for the Great Plains. Any emerging drought expansion concerns due to a drier and hotter trend for the North-central/Midwest U.S. during summer erodes during a wet autumn. The wet trend is evident for the northwest quadrant of the Gulf States to the interior Mid-Atlantic region. Most wet weather is synoptic oriented and not due to tropical cyclone activity. Fig. 14-15: The Climate Impact Company upper air/temperature/precipitation anomaly climate forecast for SEP/OCT/NOV 2023.  DEC/JAN/FEB 2023-24: The winter 2023-24 outlook looks interesting with an upper trough across the Southwest U.S. and a blocking ridge over Greenland. The forecast indicates a moderately chilly winter across the Great Plains to the Northwest States while the Southeast is warm. The Southwest States may be cooler/wetter than indicated. A stormy winter in the East but favoring more rain than snow. Fig. 16-17: The Climate Impact Company upper air/temperature/precipitation anomaly climate forecast for DEC/JAN/FEB 2023-24.