Extreme Heatwaves Summary Table
in Maryland: January 1 - August 22, 2026
Data source: NOAA nClimGrid-Daily dataset (19912020 Climatology)
| Region | No. of Hot Days/Nights | Climatological No. of Hot Days/Nights | No. of Joint Hot Days/Nights | Mean Temp among all Joint Hot Days/Nigths | Maxium Temp among all Joint Hot Days/Nigths | Day when Max Temp among all Joint Hot Days occurred | No. of Heatwaves (#) | Mean Duration of Heatwaves (days) | Longest Heatwave (days) | Start of the First Heatwave | Start of Last Heatwave | Mean Temp of all Temps in Heatwaves | Mean Temp of Heatwaves' Mean Temps | Max Temp of Heatwaves' Mean Temps | Number of Heatwave when Max Temp of Heatwaves' Mean Temps occurred | Max Temp within all Heatwaves | Day when Max Temp within all Heatwaves occurred |
|---|
| Maryland Statewide | 24 / 19 | 12.6 / 12.7 | 16 | 89.1 / 62.3 | 100.1 / 76.2 | 4 Jul / 3 Jul | 2 | 3.5 | 4 | 15 Apr | 2 Jul | 81.0 | 80.1 | 86.3 | 2.0 | 100.1 | 4 Jul |
| Climate Division 1 | 28 / 24 | 12.4 / 12.2 | 16 | 86.9 / 62.3 | 101.0 / 76.0 | 4 Jul / 4 Jul | 1 | 4.0 | 4 | 15 Apr | 15 Apr | 72.4 | 72.4 | 72.4 | 1.0 | 88.0 | 16 Apr |
| Climate Division 2 | 25 / 25 | 12.5 / 12.6 | 17 | 90.1 / 63.7 | 102.5 / 77.6 | 5 Jul / 4 Jul | 3 | 3.0 | 3 | 15 Apr | 3 Jul | 81.3 | 81.3 | 88.8 | 3.0 | 102.5 | 5 Jul |
| Climate Division 3 | 21 / 18 | 12.5 / 12.2 | 15 | 89.5 / 64.2 | 100.8 / 78.3 | 5 Jul / 4 Jul | 2 | 3.0 | 3 | 19 May | 3 Jul | 84.5 | 84.5 | 88.5 | 2.0 | 100.8 | 5 Jul |
| Climate Division 4 | 23 / 17 | 12.6 / 12.6 | 15 | 90.1 / 63.3 | 101.3 / 78.8 | 4 Jul / 3 Jul | 2 | 3.0 | 3 | 15 Apr | 2 Jul | 81.8 | 81.8 | 88.5 | 2.0 | 101.3 | 4 Jul |
| Climate Division 5 | 25 / 24 | 12.4 / 12.8 | 16 | 91.2 / 65.0 | 102.3 / 78.4 | 4 Jul / 4 Jul | 2 | 3.5 | 4 | 15 Apr | 2 Jul | 82.5 | 81.5 | 88.4 | 2.0 | 102.3 | 4 Jul |
| Climate Division 6 | 23 / 22 | 12.4 / 12.4 | 15 | 89.4 / 61.5 | 100.5 / 77.3 | 4 Jul / 3 Jul | 2 | 3.0 | 3 | 15 Apr | 2 Jul | 81.1 | 81.1 | 87.5 | 2.0 | 100.5 | 4 Jul |
| Climate Division 7 | 21 / 24 | 12.7 / 12.4 | 13 | 88.2 / 60.2 | 98.3 / 73.2 | 4 Jul / 3 Jul | 2 | 3.0 | 3 | 15 Apr | 2 Jul | 78.9 | 78.9 | 84.7 | 2.0 | 98.3 | 4 Jul |
| Climate Division 8 | 24 / 33 | 12.8 / 12.6 | 17 | 79.2 / 55.8 | 89.9 / 68.3 | 3 Jul / 3 Jul | 2 | 3.5 | 4 | 15 Apr | 1 Jul | 73.9 | 73.3 | 77.9 | 2.0 | 89.9 | 3 Jul |
| Allegany | 20 / 27 | 13.0 / 12.4 | 14 | 86.3 / 58.4 | 96.9 / 71.2 | 4 Jul / 3 Jul | 2 | 3.0 | 3 | 15 Apr | 2 Jul | 77.8 | 77.8 | 83.1 | 2.0 | 96.9 | 4 Jul |
| Anne Arundel | 23 / 16 | 12.7 / 12.5 | 14 | 90.5 / 64.8 | 101.4 / 79.3 | 4 Jul / 3 Jul | 2 | 3.0 | 3 | 15 Apr | 2 Jul | 81.9 | 81.9 | 88.8 | 2.0 | 101.4 | 4 Jul |
| Baltimore | 23 / 23 | 12.6 / 12.6 | 15 | 89.9 / 61.3 | 101.3 / 77.5 | 4 Jul / 3 Jul | 2 | 3.0 | 3 | 15 Apr | 2 Jul | 81.4 | 81.4 | 87.9 | 2.0 | 101.3 | 4 Jul |
| Calvert | 22 / 19 | 12.6 / 12.3 | 15 | 89.2 / 64.0 | 100.7 / 78.1 | 5 Jul / 4 Jul | 2 | 3.0 | 3 | 19 May | 3 Jul | 84.2 | 84.2 | 88.2 | 2.0 | 100.7 | 5 Jul |
| Caroline | 24 / 25 | 12.7 / 12.3 | 16 | 92.1 / 64.4 | 103.3 / 77.6 | 5 Jul / 4 Jul | 3 | 3.0 | 3 | 15 Apr | 3 Jul | 81.9 | 82.0 | 89.2 | 3.0 | 103.3 | 5 Jul |
| Carroll | 22 / 22 | 13.1 / 12.4 | 15 | 88.8 / 60.3 | 99.7 / 75.9 | 4 Jul / 3 Jul | 2 | 3.0 | 3 | 15 Apr | 2 Jul | 80.3 | 80.3 | 86.3 | 2.0 | 99.7 | 4 Jul |
| Cecil | 25 / 27 | 12.7 / 12.6 | 18 | 90.7 / 64.2 | 101.8 / 78.1 | 3 Jul / 3 Jul | 2 | 4.0 | 4 | 14 Apr | 2 Jul | 80.5 | 80.5 | 88.1 | 2.0 | 101.8 | 3 Jul |
| Charles | 22 / 16 | 12.7 / 12.2 | 14 | 90.1 / 64.2 | 101.3 / 78.7 | 4 Jul / 4 Jul | 1 | 3.0 | 3 | 2 Jul | 2 Jul | 88.4 | 88.4 | 88.4 | 1.0 | 101.3 | 4 Jul |
| Dorchester | 27 / 22 | 12.7 / 12.6 | 16 | 90.0 / 64.3 | 102.3 / 77.4 | 5 Jul / 4 Jul | 2 | 3.0 | 3 | 19 May | 3 Jul | 84.6 | 84.6 | 88.5 | 2.0 | 102.3 | 5 Jul |
| Frederick | 21 / 21 | 12.6 / 12.3 | 15 | 88.9 / 61.4 | 99.5 / 76.6 | 4 Jul / 3 Jul | 2 | 3.0 | 3 | 15 Apr | 2 Jul | 80.7 | 80.7 | 86.8 | 2.0 | 99.5 | 4 Jul |
| Garrett | 24 / 33 | 12.9 / 12.6 | 17 | 79.2 / 55.8 | 90.0 / 68.3 | 4 Jul / 3 Jul | 2 | 3.5 | 4 | 15 Apr | 1 Jul | 74.0 | 73.3 | 78.0 | 2.0 | 90.0 | 4 Jul |
| Harford | 23 / 24 | 12.9 / 12.5 | 17 | 90.3 / 63.0 | 101.8 / 78.3 | 3 Jul / 3 Jul | 2 | 3.5 | 4 | 15 Apr | 2 Jul | 82.3 | 81.4 | 88.2 | 2.0 | 101.8 | 3 Jul |
| Howard | 22 / 20 | 12.8 / 12.2 | 15 | 89.6 / 61.5 | 100.2 / 77.1 | 4 Jul / 3 Jul | 2 | 3.0 | 3 | 15 Apr | 2 Jul | 81.0 | 81.0 | 87.1 | 2.0 | 100.2 | 4 Jul |
| Kent | 25 / 21 | 12.5 / 12.5 | 14 | 89.9 / 64.3 | 102.1 / 78.6 | 4 Jul / 4 Jul | 2 | 3.0 | 3 | 15 Apr | 2 Jul | 81.6 | 81.6 | 88.6 | 2.0 | 102.1 | 4 Jul |
| Montgomery | 23 / 20 | 13.0 / 12.5 | 15 | 89.7 / 62.8 | 99.8 / 77.6 | 4 Jul / 3 Jul | 2 | 3.0 | 3 | 15 Apr | 2 Jul | 81.4 | 81.4 | 87.4 | 2.0 | 99.8 | 4 Jul |
| Prince George's | 22 / 17 | 12.6 / 12.6 | 15 | 90.2 / 63.1 | 101.2 / 78.3 | 4 Jul / 3 Jul | 2 | 3.0 | 3 | 15 Apr | 2 Jul | 81.7 | 81.7 | 88.2 | 2.0 | 101.2 | 4 Jul |
| Queen Anne's | 25 / 24 | 12.5 / 12.9 | 16 | 91.4 / 65.1 | 102.5 / 78.3 | 4 Jul / 4 Jul | 2 | 3.5 | 4 | 15 Apr | 2 Jul | 82.5 | 81.5 | 88.3 | 2.0 | 102.5 | 4 Jul |
| Somerset | 24 / 21 | 12.3 / 12.1 | 14 | 87.4 / 63.5 | 100.8 / 76.6 | 5 Jul / 4 Jul | 0 | 0.0 | 0 | - | - | - | - | - | - | - | - |
| St. Mary's | 20 / 20 | 12.3 / 12.2 | 16 | 89.0 / 64.6 | 100.6 / 78.0 | 5 Jul / 4 Jul | 2 | 3.0 | 3 | 19 May | 3 Jul | 84.2 | 84.2 | 88.1 | 2.0 | 100.6 | 5 Jul |
| Talbot | 24 / 27 | 12.7 / 12.5 | 16 | 90.8 / 65.2 | 102.3 / 78.2 | 5 Jul / 4 Jul | 3 | 3.0 | 3 | 15 Apr | 3 Jul | 81.2 | 81.2 | 89.0 | 3.0 | 102.3 | 5 Jul |
| Washington | 21 / 23 | 12.8 / 12.6 | 14 | 88.5 / 59.7 | 99.7 / 75.1 | 4 Jul / 3 Jul | 2 | 3.0 | 3 | 15 Apr | 2 Jul | 80.0 | 80.0 | 86.3 | 2.0 | 99.7 | 4 Jul |
| Wicomico | 28 / 23 | 12.5 / 12.1 | 16 | 89.3 / 63.1 | 102.2 / 75.9 | 5 Jul / 4 Jul | 2 | 3.0 | 3 | 15 Apr | 3 Jul | 80.7 | 80.7 | 87.7 | 2.0 | 102.2 | 5 Jul |
| Worcester | 30 / 26 | 12.3 / 12.8 | 17 | 86.1 / 62.6 | 100.5 / 75.5 | 4 Jul / 4 Jul | 1 | 4.0 | 4 | 15 Apr | 15 Apr | 72.0 | 72.0 | 72.0 | 1.0 | 87.4 | 16 Apr |
| Baltimore city | 22 / 17 | 12.4 / 12.6 | 14 | 91.2 / 64.4 | 102.2 / 80.0 | 4 Jul / 3 Jul | 2 | 3.0 | 3 | 15 Apr | 2 Jul | 82.6 | 82.6 | 89.5 | 2.0 | 102.2 | 4 Jul |