Real-time measurements are usually taken in the periphery of the cyclone, where conditions are less catastrophic and its true strength cannot be evaluated. For this reason, there are teams of meteorologists that move into the path of tropical cyclones to help evaluate their strength at the point of landfall.Tropical cyclones are tracked by weather satellites capturing visible and infrared images from space, usually at half-hour to quarter-hour intervals. As a storm approaches land, it can be observed by land-based Doppler weather radar. Radar plays a crucial role around landfall by showing a storms location and intensity every several minutes. Other satellites provide information from the perturbations of GPS signals, providing thousands of snapshots per day and capturing atmospheric temperature, pressure, and moisture content.In situ measurements, in real-time, can be taken by sending specially equipped reconnaissance flights into the cyclone. In the Atlantic basin, these flights are regularly flown by United States government hurricane hunters. These aircraft fly directly into the cyclone and take direct and remote-sensing measurements. The aircraft also launch GPS dropsondes inside the cyclone. These sondes measure temperature, humidity, pressure, and especially winds between flight level and the oceans surface. A new era in hurricane observation began when a remotely piloted Aerosonde, a small drone aircraft, was flown through Tropical Storm Ophelia as it passed Virginias eastern shore during the 2005 hurricane season. A similar mission was also completed successfully in the western Pacific Ocean.
Conditions that exacerbate or provoke angina
One study found that smokers with coronary artery disease had a significantly increased level of sympathetic nerve activity when compared to those without. This is in addition to increases in blood pressure, heart rate, and peripheral vascular resistance associated with nicotine, which may lead to recurrent angina attacks. In addition, the Centers for Disease Control and Prevention (CDC) reports that the risk of CHD (Coronary heart disease), stroke, and PVD (Peripheral vascular disease) is reduced within 1–2 years of smoking cessation. In another study, it was found that, after one year, the prevalence of angina in smoking men under 60 after an initial attack was 40% less in those having quit smoking compared to those that continued. Studies have found that there are short-term and long-term benefits to smoking cessation. Other medical problems
Esophageal disorders
Gastroesophageal reflux disease (GERD)
Hyperthyroidism
Hypoxemia
Profound anemia
Uncontrolled hypertension

Other cardiac problems
Bradyarrhythmia
Hypertrophic cardiomyopathy
Tachyarrhythmia
Valvular heart diseaseMyocardial ischemia can result from:

a reduction of blood flow to the heart that can be caused by stenosis, spasm, or acute occlusion (by an embolus) of the hearts arteries. resistance of the blood vessels. This can be caused by narrowing of the blood vessels; a decrease in radius. Blood flow is proportional to the radius of the artery to the fourth power. reduced oxygen-carrying capacity of the blood, due to several factors such as a decrease in oxygen tension and hemoglobin concentration.